WhatsApp is rolling out usernames so people can reach you without your phone number. You can reserve one right now under Settings > Account > Username on the latest version of the app, even though full username-based messaging doesn't switch on until later this year (country by country). Before you start typing candidates, it helps to know what the app will actually accept. Here's every rule, with examples of what passes and what gets bounced.
How long it can be
Three to 35 characters. A two-letter handle like jo is too short and gets rejected. Anything past 35 characters gets cut off or refused. Most people land somewhere in the middle, so this isn't the rule you'll trip over most.
Which characters are allowed
You get lowercase letters a-z, digits 0-9, periods (.), and underscores (_). Nothing else. No uppercase, no spaces, no emoji, no hyphens, no @.
That means Maya_Rivers fails because of the capitals, maya rivers fails because of the space, and maya-rivers fails because of the hyphen. Drop to lowercase and swap the hyphen for an underscore, and maya_rivers sails through.
It must start with a letter
Two rules work together here. Your username has to contain at least one letter, and the very first character has to be a letter.
That rules out all-number handles. 90210 won't work because there's no letter in it. 2fast won't work either, because it opens with a digit. Move the letter to the front and fast2 is fine. sam2026 works because it starts with s.
Because the first character must be a letter, you also can't lead with a period or an underscore. _alex and .alex both fail on that first character.
The period and underscore rules
Periods carry extra restrictions. You can't begin or end with one, and you can't put two in a row.
.jennyfails (starts with a period)jenny.fails (ends with a period)jen..nyfails (two periods back to back)jen.nyis fine (single period in the middle)
Underscores are looser. You can end with one and even double them up. arjun_ works, dev__arjun works, arjun_dev_ works. The only catch is the first-character rule above, so an underscore can sit anywhere except the very front.
The anti-impersonation rules
WhatsApp doesn't want handles that pose as web addresses or brands. So a username can't begin with www. and can't end with a domain-style suffix like .com or .net. Both www.mystore and coolshop.com get rejected.
Every username is also globally unique. Once someone reserves alex, that's gone, and you'll need a variation.
If you're a creator or business that already owns a username on Instagram or Facebook, you can claim the same one on WhatsApp. Link the accounts in Meta's Accounts Center and verify ownership. It only works if the handle isn't already taken on WhatsApp.
Valid vs invalid at a glance
Valid:
maya.riversdev_arjunsam2026l33t_codera_b_c
Invalid, and why:
jo: under three characters2coolforschool: starts with a digit90210: no letter anywhere.maya/maya.: period at the start or endjen..ny: two periods in a rowwww.shop: begins withwww.shop.com: ends with a domain suffixMaya_Rivers: uppercase lettersmaya rivers: contains a space
One honest note on availability
WhatsApp doesn't publish a list of taken usernames, and there's no public directory or search. The only way to find out if a handle is free is to try reserving it in the app. Any tool that claims to "check availability," PickMyHandle included, is giving you an educated guess, not a confirmed answer.
Two more things worth knowing. Because usernames aren't searchable, someone needs your exact handle to start a chat with you. And you can add an optional username key (reported as a 4-digit code) that a first-time stranger has to enter before their message reaches you. Without the key, their first message lands in a requests area instead of your chats. The key is separate from the username itself, and the details may shift by the time messaging fully launches.
PickMyHandle is an independent username generator and is not affiliated with, endorsed by, or sponsored by WhatsApp or Meta.