Android 'Message not sent: Invalid destination address' Fix

You tap send, the bubble goes grey, and a second later Android tells you Message not sent: Invalid destination address. No red exclamation on a specific contact — just that flat rejection. What's actually happening here is that the SMS framework in Android decided the number you're sending to isn't a valid destination, so it refused to hand the message to the radio. That decision happens before any network request goes out. Which means the problem is usually on your phone, not your carrier.

You'll see this most often right after restoring contacts from an old phone, importing a CSV, or pasting a number out of WhatsApp or a browser. Those workflows leave hidden characters and wrong country codes behind. Here's how to work through it.

Cause 1: The number has a bad format (hidden characters, wrong country code)

This is the one you should check first. Android's phone number parser follows ITU E.164 rules. If the string doesn't match, you get Invalid destination address. The culprits I see most:

• Non-breaking spaces pasted from a web page or PDF. They look like normal spaces but break parsing.
• A leading zero left in front of a country code, e.g. +44 07911 123456 instead of +44 7911 123456.
• Parentheses and dashes the parser can't strip out, like (555) 123-4567 copied from a US-style contact.
• Zero-width characters from a WhatsApp business card or a vCard export. They're invisible in the contact editor.
• Extension digits tacked on, e.g. +1 555 123 4567 x204.

The fix is to open the contact, wipe the number field completely, and retype it. Not paste — retype. Then pick the country code from the dropdown if your dialer has one, which forces the correct format.

If you want to verify what's actually stored, run this in Termux or adb shell:

content query --uri content://com.android.contacts/data --projection data1 --where "mimetype='vnd.android.cursor.item/phone_v2'"

Numbers with \u00a0, \u200b, or \ufeff in them are the invisible garbage. Retyping the contact is faster than hunting the character.

If the bad number is on a contact you text constantly

Delete the contact entirely and re-add it. Editing sometimes preserves the broken string in a linked profile (Google + local + SIM all merged). Deleting forces a clean write. On Samsung One UI 6 and Pixel's Contacts app this matters — both keep linked records that can mask the real stored value.

Cause 2: Your SMSC number is empty or wrong

The SMSC (Short Message Service Center) is the carrier gateway that routes your SMS. Android talks to it over the SIM. If the SMSC number stored on the SIM is blank or corrupted, the framework can't build a valid destination for the message, and you get the same error — even when the number you're texting is perfect. It looks like a contact problem but it isn't.

This happens after a SIM swap, after moving a SIM between phones, or after a carrier pushed a bad config update. Some MVNOs in particular (Mint, Visible, US Mobile) have historically left the SMSC blank on freshly provisioned SIMs.

To check it, dial:

*#*#4636#*#*

Tap Phone information, scroll to SMSC. You'll see either a number in PDU format (a long hex-ish string) or it'll be empty. If it's empty, tap Refresh, wait five seconds, then Update. If it stays empty, you need the correct SMSC from your carrier and enter it manually.

Carrier SMSC numbers change. Don't trust a 2018 forum post. Call support or use the carrier's app chat. For example, T-Mobile US has used +12063130004 for years, but AT&T has several regional ones. Entering the wrong one will break sending entirely.

One caveat: on dual-SIM phones, the *#*#4636#*#* menu often shows only one slot. Toggle the SIM you actually send from in Settings → Network → SIM cards, then re-check.

Cause 3: Broken APN or MMS config (mostly hits picture messages)

Plain SMS uses the SMSC. MMS uses your APN — the MMSC URL, MMS proxy, and MMS port. If any of those are missing or wrong, group texts and picture messages fail with the same Invalid destination address error, while plain texts go through fine. That mismatch is the tell. If your SMS works but MMS doesn't, this is your cause.

Common triggers: you flashed a custom ROM and the APN didn't carry over; you're on an MVNO that uses the host network's APN but your phone pulled the wrong one; or a carrier config update (often labeled Carrier Services in Google Play) went sideways.

To rebuild the APN manually:

1. Settings → Network & internet → SIMs → your SIM → Access Point Names.
2. Tap the three-dot menu and choose Reset to default. Reboot.
3. If that doesn't fix MMS, add a new APN with your carrier's values. Get them from your carrier's official support page — not a Reddit thread.
4. Set the APN type to include default,mms,supl (not just default). Missing mms here is a classic silent failure.
5. Save, select the new APN, reboot.

On Samsung devices there's an extra gotcha: the APN editor hides fields behind a scroll that isn't obvious. The MMS proxy and MMS port fields are below the fold. People fill in the top half, save, and wonder why group texts still fail.

Skip the "clear cache of Messages app" advice you'll see everywhere. It doesn't touch APN, SMSC, or number parsing — the three things that actually cause this error. At best it wastes two minutes.

Quick reference

Work top-down. Nine times out of ten it's the number. If it isn't, it's the SMSC. The APN only matters when SMS works but MMS doesn't — and if all three are clean and it still fails, that's a carrier provisioning issue and no amount of phone-side fiddling will help. Call them.