How to add a WhatsApp number to your email signature (with a tap-to-chat link)

Phone number or WhatsApp number — why show both

A phone number says "call me". A WhatsApp number says "message me whenever suits you". They are often the same number, but not always: plenty of businesses keep a desk line for calls and a separate number for WhatsApp, which is exactly why signatures need a field for each.

If your WhatsApp number is also your mobile, you don't need to show it twice. List it once, as WhatsApp, and leave the second phone line out.

The link that opens a chat

WhatsApp's click-to-chat link has one format: https://wa.me/ followed by the full number in international format. It has to be digits only — no plus sign, no spaces, no brackets or dashes, and no leading zeros. An Indian number written +91 97012 98999 becomes https://wa.me/919701298999.

That format is also where most mistakes happen. A number typed without its country code, such as 97012 98999, produces a link that either fails or opens a chat with someone else, because WhatsApp has no way to guess your country.

• Always include the country code (+91 for India, +971 for the UAE, +44 for the UK, and so on).
• Don't paste the link by hand if you can avoid it. A tool that builds it from the number removes the chance of a typo.
• Check it once: tap the link from a phone that isn't yours and confirm it opens the right chat.

Adding it in Mudra

Open your signature in Mudra and look under Contact. There is a field called WhatsApp (with country code), just below Mobile. Type the number the way people write it, for example +91 97012 98999, and Mudra shows it with the WhatsApp icon and builds the wa.me link for you from the digits.

It appears in every layout. The compact layout has no icons by design, so there it shows as plain text, "WhatsApp +91 97012 98999", still linked. If the field is missing a country code, the editor reminds you.

When you're done, click Copy signature and paste it over the old one in Gmail's signature settings (Settings, See all settings, General, Signature) or in Outlook. A signature you pasted earlier doesn't update by itself, so this re-paste is the step people forget.

For a whole team

If you manage signatures for a team, add a whatsapp column to the CSV you import (headers like whatsapp, whatsapp number or wa are recognised), or use the {WhatsApp} merge field in a shared design so each person's own number fills in. People without a WhatsApp number simply don't get the line.

Things worth deciding before you publish a number

A signature is seen by everyone you email, including people you've never met and anyone who later receives a forwarded copy. Use a number you're comfortable sharing that widely, ideally a business number rather than a personal one.

Set expectations too. If your WhatsApp is answered during office hours only, say so in your WhatsApp Business profile. A message that sits unanswered for two days does more harm than not offering the channel at all.

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