diff --git a/cmd/serve.go b/cmd/serve.go
index 87b83dda3..5864fa46d 100644
--- a/cmd/serve.go
+++ b/cmd/serve.go
@@ -99,6 +99,7 @@ var flagsServe = append(
 	altsrc.NewStringFlag(&cli.StringFlag{Name: "web-push-file", Aliases: []string{"web_push_file"}, EnvVars: []string{"NTFY_WEB_PUSH_FILE"}, Usage: "file used to store web push subscriptions"}),
 	altsrc.NewStringFlag(&cli.StringFlag{Name: "web-push-email-address", Aliases: []string{"web_push_email_address"}, EnvVars: []string{"NTFY_WEB_PUSH_EMAIL_ADDRESS"}, Usage: "e-mail address of sender, required to use browser push services"}),
 	altsrc.NewStringFlag(&cli.StringFlag{Name: "web-push-startup-queries", Aliases: []string{"web_push_startup_queries"}, EnvVars: []string{"NTFY_WEB_PUSH_STARTUP_QUERIES"}, Usage: "queries run when the web push database is initialized"}),
+	altsrc.NewIntFlag(&cli.IntFlag{Name: "message-limit", Aliases: []string{"message_limit"}, EnvVars: []string{"NTFY_MESSAGE_LIMIT"}, Value: server.DefaultMessageLengthLimit, Usage: "size limit for the message in bytes"}),
 )
 
 var cmdServe = &cli.Command{
@@ -189,6 +190,7 @@ func execServe(c *cli.Context) error {
 	metricsListenHTTP := c.String("metrics-listen-http")
 	enableMetrics := c.Bool("enable-metrics") || metricsListenHTTP != ""
 	profileListenHTTP := c.String("profile-listen-http")
+	messageLimit := c.Int("message-limit")
 
 	// Check values
 	if firebaseKeyFile != "" && !util.FileExists(firebaseKeyFile) {
@@ -364,6 +366,7 @@ func execServe(c *cli.Context) error {
 	conf.WebPushFile = webPushFile
 	conf.WebPushEmailAddress = webPushEmailAddress
 	conf.WebPushStartupQueries = webPushStartupQueries
+	conf.MessageLimit = messageLimit
 
 	// Set up hot-reloading of config
 	go sigHandlerConfigReload(config)
diff --git a/docs/config.md b/docs/config.md
index 9af799924..23dbeb826 100644
--- a/docs/config.md
+++ b/docs/config.md
@@ -1341,6 +1341,7 @@ variable before running the `ntfy` command (e.g. `export NTFY_LISTEN_HTTP=:80`).
 | `web-push-file`                            | `NTFY_WEB_PUSH_FILE`                            | *string*                                            | -                 | Web Push: Database file that stores subscriptions                                                                                                                                                                               |
 | `web-push-email-address`                   | `NTFY_WEB_PUSH_EMAIL_ADDRESS`                   | *string*                                            | -                 | Web Push: Sender email address                                                                                                                                                                                                  |
 | `web-push-startup-queries`                 | `NTFY_WEB_PUSH_STARTUP_QUERIES`                 | *string*                                            | -                 | Web Push: SQL queries to run against subscription database at startup                                                                                                                                                           |
+| `message-limit`                            | `NTFY_MESSAGE_LIMIT`                            | *number*                                            | -                 | The size limit (in bytes) for a ntfy message. NOTE: FCM has size limit at 4000 bytes. APNS has size limit at 4KB. If you increase this size limit, FCM and APNS will NOT work for large messages.                                                      |
 
 The format for a *duration* is: `<number>(smh)`, e.g. 30s, 20m or 1h.   
 The format for a *size* is: `<number>(GMK)`, e.g. 1G, 200M or 4000k.
diff --git a/server/server.yml b/server/server.yml
index 6b2fc989a..3e92f742c 100644
--- a/server/server.yml
+++ b/server/server.yml
@@ -357,3 +357,9 @@
 # log-level-overrides:
 # log-format: text
 # log-file:
+
+# Defines the size limit (in bytes) for a ntfy message.
+# NOTE: FCM has size limit at 4000 bytes. APNS has size limit at 4KB. If you increase this size limit, FCM and APNS will NOT work for large messages.
+# The default value is 4096 bytes.
+#
+# message-limit: