diff --git a/packages/main/src/Tab.hbs b/packages/main/src/Tab.hbs
index 50eb4be3dad5..585351c89b8b 100644
--- a/packages/main/src/Tab.hbs
+++ b/packages/main/src/Tab.hbs
@@ -1,3 +1,7 @@
 <div id="{{_id}}" class="ui5-tab-root">
-	<slot></slot>
+	<slot name="{{this._defaultSlotName}}"></slot>
+
+	{{#each tabs}}
+	<slot name="{{this._effectiveSlotName}}"></slot>
+	{{/each}}
 </div>
diff --git a/packages/main/src/Tab.js b/packages/main/src/Tab.js
index a4da30a7c5ed..1c11f0eb788a 100644
--- a/packages/main/src/Tab.js
+++ b/packages/main/src/Tab.js
@@ -21,16 +21,42 @@ import overflowCss from "./generated/themes/TabInOverflow.css.js";
  */
 const metadata = {
 	tag: "ui5-tab",
+	managedSlots: true,
+	languageAware: true,
 	slots: /** @lends sap.ui.webcomponents.main.Tab.prototype */ {
 
 		/**
-		 * Defines the tab content.
+		 * Holds the content associated with this tab.
+		 *
 		 * @type {Node[]}
-		 * @slot
 		 * @public
+		 * @slot
 		 */
 		"default": {
 			type: Node,
+			propertyName: "content",
+			invalidateOnChildChange: {
+				properties: true,
+				slots: false,
+			},
+		},
+
+		/**
+		 * Defines hierarchies with nested sub tabs.
+		 * <br><br>
+		 * <b>Note:</b> Use <code>ui5-tab</code> and <code>ui5-tab-separator</code> for the intended design.
+		 *
+		 * @type {sap.ui.webcomponents.main.ITab[]}
+		 * @public
+		 * @slot subTabs
+		 */
+		subTabs: {
+			type: HTMLElement,
+			individualSlots: true,
+			invalidateOnChildChange: {
+				properties: true,
+				slots: false,
+			},
 		},
 	},
 	properties: /** @lends sap.ui.webcomponents.main.Tab.prototype */ {
@@ -122,6 +148,14 @@ const metadata = {
 		_selected: {
 			type: Boolean,
 		},
+
+		_realTab: {
+			type: Object,
+		},
+
+		_isTopLevelTab: {
+			type: Boolean,
+		},
 	},
 	events: /** @lends sap.ui.webcomponents.main.Tab.prototype */ {
 	},
@@ -199,6 +233,31 @@ class Tab extends UI5Element {
 		return this.getAttribute("stable-dom-ref") || `${this._id}-stable-dom-ref`;
 	}
 
+	get requiresExpandButton() {
+		return this.subTabs.length > 0 && this._isTopLevelTab && this._hasOwnContent;
+	}
+
+	get isSingleClickArea() {
+		return this.subTabs.length > 0 && this._isTopLevelTab && !this._hasOwnContent;
+	}
+
+	get isOnSelectedTabPath() {
+		return this._realTab === this || this.tabs.some(subTab => subTab.isOnSelectedTabPath);
+	}
+
+	get _effectiveSlotName() {
+		return this.isOnSelectedTabPath ? this._individualSlot : "disabled-slot";
+	}
+
+	get _defaultSlotName() {
+		return this._realTab === this ? "" : "disabled-slot";
+	}
+
+	get _hasOwnContent() {
+		return this.content.some(node => (node.nodeType !== Node.COMMENT_NODE
+				&& (node.nodeType !== Node.TEXT_NODE || node.nodeValue.trim().length !== 0)));
+	}
+
 	/**
 	 * Returns the DOM reference of the tab that is placed in the header.
 	 * <b>Note:</b> If you need a DOM ref to the tab content please use the <code>getDomRef</code> method.
@@ -238,13 +297,18 @@ class Tab extends UI5Element {
 	}
 
 	get effectiveSelected() {
-		return this.selected || this._selected;
+		const subItemSelected = this.tabs.some(elem => elem.effectiveSelected);
+		return this.selected || this._selected || subItemSelected;
 	}
 
 	get effectiveHidden() {
 		return !this.effectiveSelected;
 	}
 
+	get tabs() {
+		return this.subTabs.filter(tab => !tab.isSeparator);
+	}
+
 	get ariaLabelledBy() {
 		const labels = [];
 
@@ -298,6 +362,10 @@ class Tab extends UI5Element {
 			classes.push(`ui5-tab-strip-item--${this.design.toLowerCase()}`);
 		}
 
+		if (this.isSingleClickArea) {
+			classes.push(`ui5-tab-strip-item--singleClickArea`);
+		}
+
 		return classes.join(" ");
 	}
 
@@ -322,11 +390,15 @@ class Tab extends UI5Element {
 			classes.push("ui5-tab-overflow-item--disabled");
 		}
 
+		if (this.selected) {
+			classes.push("ui5-tab-overflow-item--selectedSubTab");
+		}
+
 		return classes.join(" ");
 	}
 
 	get overflowState() {
-		return this.disabled ? "Inactive" : "Active";
+		return (this.disabled || this.isSingleClickArea) ? "Inactive" : "Active";
 	}
 }
 
diff --git a/packages/main/src/TabContainer.hbs b/packages/main/src/TabContainer.hbs
index 3e258455c7a7..cad3aa03c046 100644
--- a/packages/main/src/TabContainer.hbs
+++ b/packages/main/src/TabContainer.hbs
@@ -66,18 +66,16 @@
 
 {{#*inline "contentArea"}}
 	<div class="{{classes.content}}" part="content">
-		{{#each items}}
-			{{#unless this.isSeparator}}
-				<div
-					class="ui5-tc__contentItem"
-					id="ui5-tc-contentItem-{{this._posinset}}"
-					?hidden="{{this.effectiveHidden}}"
-					role="tabpanel"
-					aria-labelledby="{{this._id}}"
-				>
-					<slot name="{{this._individualSlot}}"></slot>
-				</div>
-			{{/unless}}
-		{{/each}}
+		<div
+			class="ui5-tc__contentItem"
+			id="ui5-tc-content"
+			?hidden="{{this._selectedTab.effectiveHidden}}"
+			role="tabpanel"
+			aria-labelledby="{{this._selectedTab._id}}"
+		>
+			{{#each items}}
+				<slot name="{{this._effectiveSlotName}}"></slot>
+			{{/each}}
+		</div>
 	</div>
 {{/inline}}
diff --git a/packages/main/src/TabContainer.js b/packages/main/src/TabContainer.js
index f0dca43cc9b2..fc31757fd6a9 100644
--- a/packages/main/src/TabContainer.js
+++ b/packages/main/src/TabContainer.js
@@ -257,6 +257,11 @@ const metadata = {
 			type: Object,
 			multiple: true,
 		},
+
+		_overflowItems: {
+			type: Object,
+			multiple: true,
+		},
 	},
 	events: /** @lends  sap.ui.webcomponents.main.TabContainer.prototype */ {
 
@@ -291,9 +296,14 @@ const metadata = {
  * The <code>ui5-tabcontainer</code> can hold two types of entities:
  * <ul>
  * <li><code>ui5-tab</code> - contains all the information on an item (text and icon)</li>
- * <li><code>ui5-tab-separator</code> - used to separate tabs with a vertical line</li>
+ * <li><code>ui5-tab-separator</code> - used to separate tabs with a line</li>
  * </ul>
  *
+ * <h3>Hierarchies</h3>
+ * Multiple sub tabs could be placed underneath one main tab. Nesting allows deeper hierarchies with indentations
+ * to indicate the level of each nested tab. When a tab has both sub tabs and own content its click area is split
+ * to allow the user to display the content or alternatively to expand / collapse the list of sub tabs.
+ *
  * <h3>CSS Shadow Parts</h3>
  *
  * <ui5-link target="_blank" href="https://developer.mozilla.org/en-US/docs/Web/CSS/::part">CSS Shadow Parts</ui5-link> allow developers to style elements inside the Shadow DOM.
@@ -373,29 +383,18 @@ class TabContainer extends UI5Element {
 
 	onBeforeRendering() {
 		// update selected tab
-		const tabs = this._getTabs();
-		if (tabs.length) {
-			const selectedTabs = tabs.filter(tab => tab.selected);
+		this._allItemsAndSubItems = this._getAllSubItems(this.items, []);
+		if (this._allItemsAndSubItems.length) {
+			const selectedTabs = this._allItemsAndSubItems.filter(tab => tab.selected);
 			if (selectedTabs.length) {
 				this._selectedTab = selectedTabs[0];
 			} else {
-				this._selectedTab = tabs[0];
+				this._selectedTab = this._allItemsAndSubItems[0];
 				this._selectedTab._selected = true;
 			}
 		}
 
-		// Set external properties to items
-		this.items.filter(item => !item.isSeparator).forEach((item, index, arr) => {
-			item._isInline = this.tabLayout === TabLayout.Inline;
-			item._mixedMode = this.mixedMode;
-			item._posinset = index + 1;
-			item._setsize = arr.length;
-			item._getTabContainerHeaderItemCallback = _ => {
-				return this.getDomRef().querySelector(`#${item._id}`);
-			};
-			item._itemSelectCallback = this._onItemSelect.bind(this);
-			item._getRealDomRef = () => this.getDomRef().querySelector(`*[data-ui5-stable=${item.stableDomRef}]`);
-		});
+		this._setItemsExternalProperties(this.items);
 
 		if (!this._animationRunning) {
 			this._contentCollapsed = this.collapsed;
@@ -420,15 +419,94 @@ class TabContainer extends UI5Element {
 		ResizeHandler.deregister(this._getHeader(), this._handleResize);
 	}
 
-	_onTabStripClick(event) {
+	_setItemsExternalProperties(items) {
+		items.filter(item => !item.isSeparator).forEach((item, index, arr) => {
+			item._isInline = this.tabLayout === TabLayout.Inline;
+			item._mixedMode = this.mixedMode;
+			item._posinset = index + 1;
+			item._setsize = arr.length;
+			item._getTabContainerHeaderItemCallback = _ => this.getDomRef().querySelector(`#${item._id}`);
+			item._itemSelectCallback = this._onItemSelect.bind(this);
+			item._getRealDomRef = () => this.getDomRef().querySelector(`*[data-ui5-stable=${item.stableDomRef}]`);
+			item._realTab = this._selectedTab;
+			item._isTopLevelTab = this.items.some(i => i === item);
+			walk(items, tab => {
+				tab._realTab = item._realTab;
+			});
+		});
+	}
+
+	async _onTabStripClick(event) {
 		const tab = getTab(event.target);
 		if (!tab) {
 			return;
 		}
+		event.preventDefault();
+		event.stopPropagation();
+		if (event.target.hasAttribute("ui5-button")) {
+			this._onTabExpandButtonClick(event);
+			return;
+		}
+
+		if (!tab._realTab._hasOwnContent && tab._realTab.tabs.length) {
+			this._overflowItems = [];
+			this._overflowItems = tab._realTab.subTabs;
+			this._addStyleIndent(this._overflowItems, false);
+
+			this.responsivePopover = await this._respPopover();
+			if (this.responsivePopover.opened) {
+				this.responsivePopover.close();
+			} else {
+				this._setInitialFocus(this._getSelectedInPopover());
+			}
 
+			this.responsivePopover.showAt(tab);
+			return;
+		}
 		this._onHeaderItemSelect(tab);
 	}
 
+	async _onTabExpandButtonClick(event) {
+		event.stopPropagation();
+		event.preventDefault();
+		let button = event.target;
+		let tabInstance = button.tab;
+
+		if (tabInstance) {
+			tabInstance.focus();
+		}
+
+		if ((event.type === "keydown") && !event.target._realTab.isSingleClickArea) {
+			button = event.target.querySelectorAll(".ui5-tab-expand-button")[0];
+			tabInstance = event.target._realTab;
+		}
+
+		// if clicked between the expand button and the tab
+		if (!tabInstance) {
+			this._onHeaderItemSelect(button.parentElement);
+			return;
+		}
+
+		this._overflowItems = tabInstance.subTabs;
+		this._addStyleIndent(this._overflowItems, false);
+
+		this.responsivePopover = await this._respPopover();
+		if (this.responsivePopover.opened) {
+			this.responsivePopover.close();
+		} else {
+			this._setInitialFocus(this._getSelectedInPopover());
+		}
+		this.responsivePopover.showAt(button);
+	}
+
+	_setInitialFocus(selectedInPopover) {
+		if (selectedInPopover.length) {
+			this.responsivePopover.initialFocus = selectedInPopover[0].id;
+		} else {
+			this.responsivePopover.initialFocus = this.responsivePopover.content[0].items.filter(item => item.classList.contains("ui5-tab-overflow-item"))[0].id;
+		}
+	}
+
 	_onTabStripKeyDown(event) {
 		const tab = getTab(event.target);
 		if (!tab) {
@@ -436,12 +514,24 @@ class TabContainer extends UI5Element {
 		}
 
 		if (isEnter(event)) {
-			this._onHeaderItemSelect(tab);
+			if (tab._realTab.isSingleClickArea) {
+				this._onTabStripClick(event);
+			} else {
+				this._onHeaderItemSelect(tab);
+			}
 		}
 
-		// Prevent Scrolling
 		if (isSpace(event)) {
-			event.preventDefault();
+			event.preventDefault(); // prevent scrolling
+		}
+
+		if (isDown(event)) {
+			if (tab._realTab.requiresExpandButton) {
+				this._onTabExpandButtonClick(event);
+			}
+			if (tab._realTab.isSingleClickArea) {
+				this._onTabStripClick(event);
+			}
 		}
 	}
 
@@ -452,7 +542,12 @@ class TabContainer extends UI5Element {
 		}
 
 		if (isSpace(event)) {
-			this._onHeaderItemSelect(tab);
+			event.preventDefault();
+			if (tab._realTab.isSingleClickArea) {
+				this._onTabStripClick(event);
+			} else {
+				this._onHeaderItemSelect(tab);
+			}
 		}
 	}
 
@@ -466,23 +561,40 @@ class TabContainer extends UI5Element {
 		}
 	}
 
-	_onOverflowListItemClick(event) {
+	async _onOverflowListItemClick(event) {
 		event.preventDefault(); // cancel the item selection
 		const { item } = event.detail;
 
 		this._onItemSelect(item);
-		this.responsivePopover.close();
+		await this.responsivePopover.close();
+
 		this._setItemsForStrip();
-		this.shadowRoot.querySelector(`#${item.id}`).focus();
+
+		const selectedTopLevel = this._getRootTab(this._selectedTab);
+
+		selectedTopLevel.focus();
+	}
+
+	_getAllSubItems(items, result, level = 1) {
+		items.forEach(item => {
+			if (item.hasAttribute("ui5-tab") || item.hasAttribute("ui5-tab-separator")) {
+				item._level = level;
+				result.push(item);
+				if (item.subTabs) {
+					this._getAllSubItems(item.subTabs, result, level + 1);
+				}
+			}
+		});
+		return result;
 	}
 
 	_onItemSelect(target) {
-		const selectedIndex = findIndex(this.items, item => item._id === target.id);
-		const selectedTabIndex = findIndex(this._getTabs(), item => item._id === target.id);
-		const selectedTab = this.items[selectedIndex];
+		const selectedIndex = findIndex(this._allItemsAndSubItems, item => item.__id === target.id);
+		const selectedTabIndex = findIndex(this._allItemsAndSubItems, item => item.__id === target.id);
+		const selectedTab = this._allItemsAndSubItems[selectedIndex];
 
 		// update selected items
-		this.items
+		this._allItemsAndSubItems
 			.forEach((item, index) => {
 				const selected = selectedIndex === index;
 				item.selected = selected;
@@ -566,8 +678,7 @@ class TabContainer extends UI5Element {
 
 		const overflowAttr = isEndOverflow ? "end-overflow" : "start-overflow";
 
-		this._startOverflowItems = [];
-		this._endOverflowItems = [];
+		this._overflowItems = [];
 
 		this.items.forEach(item => {
 			if (item.getTabInStripDomRef() && item.getTabInStripDomRef().hasAttribute(overflowAttr)) {
@@ -578,12 +689,14 @@ class TabContainer extends UI5Element {
 		let button;
 		if (isEndOverflow) {
 			button = this.overflowButton[0] || overflow.querySelector("[ui5-button]");
-			this._endOverflowItems = items;
+			this._overflowItems = items;
+			this._addStyleIndent(this._overflowItems, true);
 		}
 
 		if (isStartOverflow) {
 			button = this.startOverflowButton[0] || overflow.querySelector("[ui5-button]");
-			this._startOverflowItems = items;
+			this._overflowItems = items;
+			this._addStyleIndent(this._overflowItems, true);
 		}
 
 		this.responsivePopover = await this._respPopover();
@@ -595,14 +708,32 @@ class TabContainer extends UI5Element {
 		}
 	}
 
+	_getSelectedInPopover() {
+		return this.responsivePopover.content[0].items.filter(item => (item._realTab && item._realTab.selected));
+	}
+
+	_addStyleIndent(tabs, isOverflow) {
+		walk(tabs, tab => {
+			let level = tab._level;
+			if (!isOverflow) {
+				level -= 1;
+			}
+
+			if (tab._level > 1 && tab.isSeparator) {
+				level -= 1;
+			}
+
+			tab._style = {
+				"--_ui5-indentation-level": level / 2,
+			};
+		});
+	}
+
 	async _onOverflowKeyDown(event) {
 		const isEndOverflow = event.currentTarget.classList.contains("ui5-tc__overflow--end");
 		const isStartOverflow = event.currentTarget.classList.contains("ui5-tc__overflow--start");
 
-		switch (true) {
-		case isDown(event):
-		case isStartOverflow && isLeft(event):
-		case isEndOverflow && isRight(event):
+		if (isDown(event) || (isStartOverflow && isLeft(event)) || (isEndOverflow && isRight(event))) {
 			await this._onOverflowClick(event);
 		}
 	}
@@ -657,14 +788,24 @@ class TabContainer extends UI5Element {
 		}
 
 		this._itemNavigation._init();
-		this._itemNavigation.setCurrentItem(this._selectedTab);
+		this._itemNavigation.setCurrentItem(this._getRootTab(this._selectedTab));
+	}
+
+	_getRootTab(tab) {
+		while (tab.hasAttribute("ui5-tab")) {
+			if (tab.parentElement.hasAttribute("ui5-tabcontainer")) {
+				break;
+			}
+			tab = tab.parentElement;
+		}
+		return tab;
 	}
 
 	_updateEndOverflow(itemsDomRefs) {
 		// show end overflow
 		this._getEndOverflow().removeAttribute("hidden");
-
-		const selectedTabDomRef = this._selectedTab.getTabInStripDomRef();
+		const selectedTab = this._getRootTab(this._selectedTab);
+		const selectedTabDomRef = selectedTab.getTabInStripDomRef();
 		const containerWidth = this._getTabStrip().offsetWidth;
 
 		const selectedItemIndexAndWidth = this._getSelectedItemIndexAndWidth(itemsDomRefs, selectedTabDomRef);
@@ -680,7 +821,8 @@ class TabContainer extends UI5Element {
 
 	_updateStartAndEndOverflow(itemsDomRefs) {
 		let containerWidth = this._getTabStrip().offsetWidth;
-		const selectedTabDomRef = this._selectedTab.getTabInStripDomRef();
+		const selectedTab = this._getRootTab(this._selectedTab);
+		const selectedTabDomRef = selectedTab.getTabInStripDomRef();
 		const selectedItemIndexAndWidth = this._getSelectedItemIndexAndWidth(itemsDomRefs, selectedTabDomRef);
 		const hasStartOverflow = this._hasStartOverflow(containerWidth, itemsDomRefs, selectedItemIndexAndWidth);
 		const hasEndOverflow = this._hasEndOverflow(containerWidth, itemsDomRefs, selectedItemIndexAndWidth);
@@ -1088,6 +1230,15 @@ const findIndex = (arr, predicate) => {
 	return -1;
 };
 
+const walk = (tabs, callback) => {
+	[...tabs].forEach(tab => {
+		callback(tab);
+		if (tab.subTabs) {
+			walk(tab.subTabs, callback);
+		}
+	});
+};
+
 TabContainer.define();
 
 export default TabContainer;
diff --git a/packages/main/src/TabContainerPopover.hbs b/packages/main/src/TabContainerPopover.hbs
index 29f47bd14f49..b6234c095a71 100644
--- a/packages/main/src/TabContainerPopover.hbs
+++ b/packages/main/src/TabContainerPopover.hbs
@@ -8,15 +8,9 @@
 	class="ui5-tab-container-responsive-popover"
 >
 	<ui5-list mode="SingleSelect" separators="None" @ui5-item-click="{{_onOverflowListItemClick}}">
-		{{#if _endOverflowItems.length}}
-			{{#each _endOverflowItems}}
-				{{this.overflowPresentation}}
-			{{/each}}
-		{{else}}
-			{{#each _startOverflowItems}}
-				{{this.overflowPresentation}}
-			{{/each}}
-		{{/if}}
+		{{#each _overflowItems}}
+			{{overflowPresentation}}
+		{{/each}}
 	</ui5-list>
 	<div slot="footer" class="ui5-responsive-popover-footer">
 		<ui5-button
@@ -24,4 +18,4 @@
 			@click="{{_closeRespPopover}}"
 		>{{popoverCancelButtonText}}</ui5-button>
 	</div>
-</ui5-responsive-popover>
+</ui5-responsive-popover>
\ No newline at end of file
diff --git a/packages/main/src/TabInOverflow.hbs b/packages/main/src/TabInOverflow.hbs
index bbc4752c47d3..b2aa90daf88c 100644
--- a/packages/main/src/TabInOverflow.hbs
+++ b/packages/main/src/TabInOverflow.hbs
@@ -6,16 +6,23 @@
 	aria-disabled="{{this.effectiveDisabled}}"
 	aria-selected="{{this.effectiveSelected}}"
 	aria-labelledby="{{this.ariaLabelledBy}}"
+	._realTab="{{this}}"
+	style="{{this._style}}"
 >
-	<div class="ui5-tab-overflow-itemContent">
-		{{#if this.icon}}
-			<ui5-icon name="{{this.icon}}"></ui5-icon>
-		{{/if}}
+	<div class="ui5-tab-overflow-itemContent-wrapper">
+		<div class="ui5-tab-overflow-itemContent">
+			{{#if this.icon}}
+				<ui5-icon name="{{this.icon}}"></ui5-icon>
+			{{/if}}
 
-		{{this.text}}
+			{{this.text}}
 
-		{{#if this.additionalText}}
-			({{this.additionalText}})
-		{{/if}}
+			{{#if this.additionalText}}
+				({{this.additionalText}})
+			{{/if}}
+		</div>
 	</div>
 </ui5-li-custom>
+{{#each subTabs}}
+	{{overflowPresentation}}
+{{/each}}
diff --git a/packages/main/src/TabInStrip.hbs b/packages/main/src/TabInStrip.hbs
index 9f4cc9e7f2e6..54b4286fb9ec 100644
--- a/packages/main/src/TabInStrip.hbs
+++ b/packages/main/src/TabInStrip.hbs
@@ -4,12 +4,13 @@
 	role="tab"
 	aria-posinset="{{this._posinset}}"
 	aria-setsize="{{this._setsize}}"
-	aria-controls="ui5-tc-contentItem-{{this._posinset}}"
+	aria-controls="ui5-tc-content"
 	aria-selected="{{this.effectiveSelected}}"
 	aria-disabled="{{this.effectiveDisabled}}"
 	?disabled="{{this.effectiveDisabled}}"
 	aria-labelledby="{{this.ariaLabelledBy}}"
 	data-ui5-stable="{{this.stableDomRef}}"
+	._realTab="{{this}}"
 >
 	{{#if this.icon}}
 		<div class="ui5-tab-strip-item-icon-outer">
@@ -26,10 +27,26 @@
 			<span class="ui5-tab-strip-itemText" id="{{this._id}}-text">
 				<span class="{{this.headerSemanticIconClasses}}"></span>
 				{{this.displayText}}
+			{{#if this.isSingleClickArea}}
+			<span class="ui5-tab-single-click-icon">
+				<ui5-icon name="slim-arrow-down"></ui5-icon>
+			</span>
+			{{/if}}
 			</span>
 		{{/if}}
+
 	</div>
-</div>
+	{{#if this.requiresExpandButton}}
+		<div class="ui5-tab-expand-button" @click="{{_onTabExpandButtonClick}}">
+			<ui5-button
+				.tab={{this}}
+				icon="slim-arrow-down"
+				design="Transparent"
+				tabindex="-1"
+				aria-haspopup="true">
+			</ui5-button>
+		</div>
+	{{/if}}
 
 {{#*inline additionalText}}
 	{{#if this.additionalText}}
diff --git a/packages/main/src/TabSeparatorInOverflow.hbs b/packages/main/src/TabSeparatorInOverflow.hbs
index f9abf06039b8..cb1e353bc2da 100644
--- a/packages/main/src/TabSeparatorInOverflow.hbs
+++ b/packages/main/src/TabSeparatorInOverflow.hbs
@@ -4,5 +4,6 @@
 	role="separator"
 	class="{{classes}}"
 	disabled
+	style="{{this._style}}"
 >
 </ui5-li-custom>
\ No newline at end of file
diff --git a/packages/main/src/themes/TabContainer.css b/packages/main/src/themes/TabContainer.css
index 7a6ac9c53291..1fc4c624891c 100644
--- a/packages/main/src/themes/TabContainer.css
+++ b/packages/main/src/themes/TabContainer.css
@@ -103,6 +103,27 @@
 	display: none;
 }
 
+.ui5-tab-expand-button > [ui5-button] {
+	height: 1.5rem;
+	min-width: 1.5rem;
+	margin-top: 0.25rem;
+	margin-left: 0.625rem;
+}
+.ui5-tab-single-click-icon {
+	margin-left: 0.625rem;
+	float: right;
+}
+
+.ui5-tab-strip-item--singleClickArea {
+	margin-top: 2px;
+}
+
+.ui5-tab-expand-button>[ui5-button]:hover {
+	background-color: var(--sapButton_Hover_Background);
+}
+.ui5-tab-expand-button>[ui5-button]:active {
+	background-color: var(--sapButton_Active_Background);
+}
 /*** Responsive paddings ***/
 
 :host([media-range="S"]) .ui5-tc__header {
diff --git a/packages/main/src/themes/TabInOverflow.css b/packages/main/src/themes/TabInOverflow.css
index 732a58c05ed3..b89148e1827e 100644
--- a/packages/main/src/themes/TabInOverflow.css
+++ b/packages/main/src/themes/TabInOverflow.css
@@ -34,9 +34,18 @@
 .ui5-tab-overflow-itemContent {
 	display: flex;
 	align-items: center;
-	padding: 0 0.5rem;
+	padding-right: 0.5rem;
 	height: var(--_ui5_tc_item_text);
 	pointer-events: none;
+	font-size: 0.875rem;
+}
+
+.ui5-tab-overflow-itemContent-wrapper {
+	padding-left: calc(var(--_ui5-indentation-level, 0) * 1rem);
+}
+
+.ui5-tab-overflow-item--selectedSubTab {
+	background-color: var(--sapList_SelectionBackgroundColor);
 }
 
 .ui5-tab-overflow-item [ui5-icon] {
diff --git a/packages/main/src/themes/TabInStrip.css b/packages/main/src/themes/TabInStrip.css
index 293e91ebb1be..3eaff8a01b8b 100644
--- a/packages/main/src/themes/TabInStrip.css
+++ b/packages/main/src/themes/TabInStrip.css
@@ -44,15 +44,14 @@
 .ui5-tab-strip-item--selected.ui5-tab-strip-item--textOnly {
 	color: var(--_ui5_tc_headeritem_text_selected_color);
 }
+.ui5-tab-strip-item--selected .ui5-tab-single-click-icon>[ui5-icon] {
+	color: var(--_ui5_tc_headeritem_text_selected_color);
+}
 
 .ui5-tab-strip-item:hover:not(.ui5-tab-strip-item--selected).ui5-tab-strip-item--textOnly {
 	color: var(--_ui5_tc_headerItem_text_hover_color);
 }
 
-.ui5-tab-strip-item:hover.ui5-tab-strip-item--selected.ui5-tab-strip-item--textOnly {
-	color: var(--_ui5_tc_headeritem_text_selected_hover_color);
-}
-
 /* the outline when hover or selected */
 .ui5-tab-strip-item--textOnly:hover .ui5-tab-strip-itemContent::after,
 .ui5-tab-strip-item--mixedMode:hover .ui5-tab-strip-itemContent::after,
@@ -371,4 +370,16 @@
 [dir=rtl] .ui5-tab-strip-item--mixedMode .ui5-tab-strip-itemAdditionalText {
 	margin-right: 0;
 	margin-left: 0.5rem;
+}
+
+.ui5-tab-strip-item--selected:not(.ui5-tab-strip-item--withIcon) .ui5-tab-expand-button>[ui5-button]::after {
+	content: "";
+	position: absolute;
+	bottom: 1px;
+	left: 12px;
+	right: 16px;
+	border-bottom: var(--_ui5_tc_headerItemContent_border_bottom);
+	border-radius: var(--_ui5_tc_headerItemContent_border_radius);
+	background-color: var(--_ui5_tc_headerItemContent_border_bg);
+	height: var(--_ui5_tc_headerItemContent_border_height);
 }
\ No newline at end of file
diff --git a/packages/main/src/themes/TabSeparatorInOverflow.css b/packages/main/src/themes/TabSeparatorInOverflow.css
index ce23450dd07d..67166a187a5a 100644
--- a/packages/main/src/themes/TabSeparatorInOverflow.css
+++ b/packages/main/src/themes/TabSeparatorInOverflow.css
@@ -1,7 +1,8 @@
 .ui5-tc__separator {
 	min-height: 0.25rem;
 	border-bottom: 0.0625rem solid var(--sapGroup_TitleBorderColor);
-	margin: 0 0.5rem;
+	margin-left: calc(var(--_ui5-indentation-level, 0) * 1rem);
+	margin-right: 0.5rem;
 }
 [ui5-list]>.ui5-tc__separator:first-child {
 	min-height: 0.5rem;
diff --git a/packages/main/test/pages/TabContainer.html b/packages/main/test/pages/TabContainer.html
index 463b5d4f739e..3df3a1c27606 100644
--- a/packages/main/test/pages/TabContainer.html
+++ b/packages/main/test/pages/TabContainer.html
@@ -26,14 +26,116 @@
 	<header class="header">
 		<h1 class="header-title">ui5-tabcontainer</h1>
 	</header>
+	<ui5-toggle-button id="densityToggle">Compact</ui5-toggle-button>
+	<section>
+		<h2>Nested Tabs</h2>
+		<ui5-tabcontainer id="tabContainerNestedTabs" collapsed>
+			<ui5-tab text="One">
+				<ui5-button>Button 1</ui5-button>
+			</ui5-tab>
+				<ui5-tab-separator></ui5-tab-separator>
+			<ui5-tab text="Two">
+					<ui5-button id="button2">Button 2</ui5-button>
+				<ui5-tab slot="subTabs" text="2.1">
+					<ui5-button id="button21">Button 21</ui5-button>
+
+					<ui5-tab slot="subTabs" text="2.1.1" selected>
+						<ui5-button id="button211">Button 211</ui5-button>
+				<ui5-tab-separator slot="subTabs"></ui5-tab-separator>
+					</ui5-tab>
+
+					<ui5-tab slot="subTabs" text="2.1.2">
+						<ui5-tab slot="subTabs" text="2.1.2.1">
+							<ui5-button id="button2121">Button 2121</ui5-button>
+						</ui5-tab>
+						<ui5-button id="button212">Button 212</ui5-button>
+					</ui5-tab>
+				</ui5-tab>
+
+				<ui5-tab text="2.2" slot="subTabs">
+					Text for 2.2
+				</ui5-tab>
+			</ui5-tab>
+
+			<ui5-tab text="Three">
+				<ui5-tab slot="subTabs" icon="sap-icon://menu2" text="3.1">
+					<ui5-button>Button 31</ui5-button>
+				</ui5-tab>
+			</ui5-tab>
+
+			<ui5-tab text="Four"><ui5-button>Button 4</ui5-button>
+							<ui5-tab-separator slot="subTabs"></ui5-tab-separator>
+
+				<ui5-tab slot="subTabs" text="Four 1"><ui5-button>Button 41</ui5-button>
+							<ui5-tab-separator slot="subTabs"></ui5-tab-separator>
+
+					<ui5-tab slot="subTabs" text="Four 1.1"><ui5-button>Button 411</ui5-button>
+							<ui5-tab-separator slot="subTabs"></ui5-tab-separator>
+						<ui5-tab slot="subTabs" text="Four 1.1.1"><ui5-button>Button 4111</ui5-button>
+							<ui5-tab-separator slot="subTabs"></ui5-tab-separator>
+							<ui5-tab slot="subTabs" text="Four 1.1.1.1"><ui5-button>Button 41111</ui5-button></ui5-tab>
+							<ui5-tab-separator slot="subTabs"></ui5-tab-separator>
+
+						</ui5-tab>
+					</ui5-tab>
+				</ui5-tab>
+			</ui5-tab>
+
+			<ui5-tab text="Five">Tab Content</ui5-tab>
+			<ui5-tab text="Six">Tab Content</ui5-tab>
+			<ui5-tab text="Seven"></ui5-tab>
+			<ui5-tab-separator>Tab Content</ui5-tab-separator>
+			<ui5-tab text="Eight">Tab Content</ui5-tab>
+			<ui5-tab text="Nine">Tab Content</ui5-tab>
+			<ui5-tab text="Ten">Tab Content
+				<ui5-tab slot="subTabs" text="Ten 1">Tab 10.1 Content
+					<ui5-tab slot="subTabs" text="Ten 1.1">Tab 10.1.1 Content
+						<ui5-tab-separator slot="subTabs"></ui5-tab-separator>
+						<ui5-tab slot="subTabs" text="Ten 1.1.1">Tab Content
+							<ui5-tab slot="subTabs" text="Ten 1.1.1.1"></ui5-tab>
+						</ui5-tab>
+					</ui5-tab>
+				</ui5-tab>
+			</ui5-tab>
+			<ui5-tab text="Eleven"></ui5-tab>
+			<ui5-tab-separator></ui5-tab-separator>
+			<ui5-tab text="Twelve"></ui5-tab>
+			<ui5-tab text="Thirteen"></ui5-tab>
+			<ui5-tab text="Fourteen">
+				<ui5-tab slot="subTabs" text="Fourteen 1">1
+					<ui5-tab slot="subTabs" text="Fourteen 1.1">1.1</ui5-tab>
+				</ui5-tab>
+				<ui5-tab slot="subTabs" text="Fourteen 2">2
+					<ui5-tab  slot="subTabs" text="Fourteen 2.1">2.1
+						<ui5-tab slot="subTabs" text="Fourteen 2.1.1">2.1.1</ui5-tab>
+					</ui5-tab>
+					<ui5-tab slot="subTabs" text="Fourteen 2.2">2.2</ui5-tab>
+				</ui5-tab>
+			</ui5-tab>
+			<ui5-tab text="Fifteen"></ui5-tab>
+			<ui5-tab text="Sixteen"></ui5-tab>
+			<ui5-tab text="Seventeen"></ui5-tab>
+			<ui5-tab-separator></ui5-tab-separator>
+			<ui5-tab text="Eighteen"></ui5-tab>
+
+		</ui5-tabcontainer>
+	</section>
 
 	<section>
-		<ui5-toggle-button id="densityToggle">Compact</ui5-toggle-button>
 		<h2>Text only End Overflow</h2>
 		<ui5-tabcontainer id="tabContainerEndOverflow" collapsed fixed>
 			<ui5-tab text="One"></ui5-tab>
-			<ui5-tab text="Two"></ui5-tab>
-			<ui5-tab text="Three"></ui5-tab>
+			<ui5-tab text="Two">
+				<ui5-tab text="2.1"><ui5-button>Button 2.1</ui5-button>
+					<ui5-tab text="2.1.1"><ui5-button>Button 2.2</ui5-button>
+						<ui5-tab text="2.1.2"></ui5-tab><ui5-button>Button 2.3</ui5-button>
+				</ui5-tab></ui5-tab>
+			</ui5-tab>
+			<ui5-tab text="Three">
+				<ui5-tab text="3.1">
+					<ui5-button>Button 3</ui5-button>
+				</ui5-tab>
+			</ui5-tab>
 			<ui5-tab text="Four"></ui5-tab>
 			<ui5-tab text="Five"></ui5-tab>
 			<ui5-tab text="Six"></ui5-tab>
@@ -223,6 +325,7 @@ <h2>Text only</h2>
 	</section>
 
 	<section class="tabcontainer2auto">
+		<h2>Scrollable child</h2>
 		<ui5-tabcontainer fixed class="tabcontainer3auto" id="tc-scrollable-child">
 			<ui5-tab text="Tab 1" selected id="scrollable-tab">
 				<ui5-button>Toggle style</ui5-button>
@@ -549,8 +652,8 @@ <h2>No paddings for the Content</h2>
 	<section>
 		<h2>Text only Start And End Overflow Custom Overflow Buttons</h2>
 		<ui5-tabcontainer id="tabContainerCustomOverflowButtons" tabs-overflow-mode="StartAndEnd" collapsed fixed>
-						<ui5-button slot="startOverflowButton" id="startOverflowButton">Start</ui5-button>
-						<ui5-button slot="overflowButton" id="endOverflowButton">End</ui5-button>
+				<ui5-button slot="startOverflowButton" id="startOverflowButton">Start</ui5-button>
+				<ui5-button slot="overflowButton" id="endOverflowButton">End</ui5-button>
 			<ui5-tab text="One"></ui5-tab>
 			<ui5-tab text="Two"></ui5-tab>
 			<ui5-tab text="Three"></ui5-tab>
@@ -584,7 +687,6 @@ <h2>Text only Start And End Overflow Custom Overflow Buttons</h2>
 		</ui5-tabcontainer>
 	</section>
 
-
 	<script>
 		document.getElementById("tabContainer1").addEventListener("ui5-tabSelect", function (event) {
 			result.innerHTML = event.detail.tab.text;
diff --git a/packages/main/test/samples/TabContainer.sample.html b/packages/main/test/samples/TabContainer.sample.html
index 97dbf437bc4e..9c583e6c8f31 100644
--- a/packages/main/test/samples/TabContainer.sample.html
+++ b/packages/main/test/samples/TabContainer.sample.html
@@ -305,4 +305,90 @@ <h3>TabContainer with tabLayout="Inline"</h3>
 	</xmp></pre>
 </section>
 
+<!-- Nested tabs -->
+
+<section>
+	<h3>TabContainer with nested tabs</h3>
+	<div class="snippet">
+		<ui5-tabcontainer collapsed>
+			<ui5-tab text="Notes">
+				Notes go here ...
+			</ui5-tab>
+			<ui5-tab text="Products">
+				Products go here ...
+				<ui5-tab slot="subTabs" text="Computers">
+					Computers go here ...
+					<ui5-tab slot="subTabs" text="Laptops">
+						Laptops go here ...
+					</ui5-tab>
+					<ui5-tab slot="subTabs" text="Desktops">
+						<ui5-tab slot="subTabs" text="Work Stations">
+							Work Stations go here ...
+						</ui5-tab>
+						<ui5-tab slot="subTabs" text="Game Stations">
+							Game Stations go here ...
+						</ui5-tab>
+						Desktops go here ...
+					</ui5-tab>
+				</ui5-tab>
+				<ui5-tab text="Phones" slot="subTabs">
+					<ui5-tab text="Smartphones" slot="subTabs">
+						Smartphones go here ...
+					</ui5-tab>
+					<ui5-tab text="Tablets" slot="subTabs">
+						Tablets go here ...
+					</ui5-tab>
+					Phones go here ...
+				</ui5-tab>
+			</ui5-tab>
+			<ui5-tab text="Orders">
+				Orders go here ...
+				<ui5-tab slot="subTabs" text="Attachments">
+					Order attachments go here ...
+				</ui5-tab>
+			</ui5-tab>
+		</ui5-tabcontainer>
+	</div>
+	<pre class="prettyprint lang-html"><xmp>
+<ui5-tabcontainer collapsed>
+	<ui5-tab text="Notes">
+		Notes go here ...
+	</ui5-tab>
+	<ui5-tab text="Products">
+		Products go here ...
+		<ui5-tab slot="subTabs" text="Computers">
+			Computers go here ...
+			<ui5-tab slot="subTabs" text="Laptops">
+				Laptops go here ...
+			</ui5-tab>
+			<ui5-tab slot="subTabs" text="Desktops">
+				<ui5-tab slot="subTabs" text="Work Stations">
+					Work Stations go here ...
+				</ui5-tab>
+				<ui5-tab slot="subTabs" text="Game Stations">
+					Game Stations go here ...
+				</ui5-tab>
+				Desktops go here ...
+			</ui5-tab>
+		</ui5-tab>
+		<ui5-tab text="Phones" slot="subTabs">
+			<ui5-tab text="Smartphones" slot="subTabs">
+				Smartphones go here ...
+			</ui5-tab>
+			<ui5-tab text="Tablets" slot="subTabs">
+				Tablets go here ...
+			</ui5-tab>
+			Phones go here ...
+		</ui5-tab>
+	</ui5-tab>
+	<ui5-tab text="Orders">
+		Orders go here ...
+		<ui5-tab slot="subTabs" text="Attachments">
+			Order attachments go here ...
+		</ui5-tab>
+	</ui5-tab>
+</ui5-tabcontainer>
+	</xmp></pre>
+</section>
+
 <!-- JSDoc marker -->
diff --git a/packages/main/test/specs/TabContainer.spec.js b/packages/main/test/specs/TabContainer.spec.js
index f8c349f3b9e7..0901361f8083 100644
--- a/packages/main/test/specs/TabContainer.spec.js
+++ b/packages/main/test/specs/TabContainer.spec.js
@@ -23,7 +23,7 @@ describe("TabContainer general interaction", () => {
 		const resultIdx = await browser.$("#resultIdx");
 
 		const SELECTED_TAB_TEXT = "Laptops";
-		const SELECTED_TAB_INDEX = "1";
+		const SELECTED_TAB_INDEX = "2";
 
 		await item.click();
 
@@ -141,6 +141,37 @@ describe("TabContainer general interaction", () => {
 		assert.strictEqual(actualContentPadding.value, expectedContentPadding, "tabContainer has correct padding set on the content");
 	});
 
+	it("tests nested tabs", async () => {
+		const tabContainer = await browser.$("#tabContainerNestedTabs");
+		const expandButton = await tabContainer.shadow$(".ui5-tab-expand-button");
+		await expandButton.click();
+		const staticAreaItemClassName = await browser.getStaticAreaItemClassName("#tabContainerNestedTabs");
+
+		const popover = await browser.$(`.${staticAreaItemClassName}`).shadow$("ui5-responsive-popover");
+		assert.notOk(await browser.$("#button21").isDisplayed(), "Content for tab 2.1 is not displayed")
+		await (await popover.$("ui5-list").$$("ui5-li-custom"))[0].click();
+		let newlySelectedItem = await tabContainer.$("[selected]");
+		assert.strictEqual(await newlySelectedItem.getProperty("text"), "2.1", "Sub tabs are selectable and the selected tab is 2.1");
+		assert.ok(await browser.$("#button21").isDisplayed(), "Proper content for tab 2.1 is displayed")
+
+		assert.notOk(await browser.$("#button211").isDisplayed(), "Content for tab 2.1.1 is not displayed")
+		await expandButton.click();
+		await (await popover.$("ui5-list").$$("ui5-li-custom"))[1].click();
+		newlySelectedItem = await tabContainer.$("[selected]");
+			assert.notOk(await browser.$("#button21").isDisplayed(), "Content for tab 2.1 is not displayed")
+		assert.strictEqual(await newlySelectedItem.getProperty("text"), "2.1.1", "Sub tabs are selectable and the selected tab is 2.1.1");
+		assert.ok(await browser.$("#button211").isDisplayed(), "Proper content for tab 2.1.1 is displayed")
+
+		assert.notOk(await browser.$("#button2121").isDisplayed(), "Content for tab 2.1.2.1 is not displayed")
+		await expandButton.click();
+		await (await popover.$("ui5-list").$$("ui5-li-custom"))[4].click();
+		newlySelectedItem = await tabContainer.$("[selected]");
+		assert.notOk(await browser.$("#button21").isDisplayed(), "Content for tab 2.1 is not displayed")
+		assert.notOk(await browser.$("#button211").isDisplayed(), "Content for tab 2.1.1 is not displayed")
+		assert.strictEqual(await newlySelectedItem.getProperty("text"), "2.1.2.1", "Sub tabs are selectable and the selected tab is 2.1.2.1");
+		assert.ok(await browser.$("#button2121").isDisplayed(), "Proper content for tab 2.1.2.1 is displayed")
+	});
+
 	it("tests custom overflow buttons via slots", async () => {
 		await browser.setWindowSize(1000, 1080);