There are two different emails people mean by this, and they are changed in different places.
Your own login email
You cannot edit the email address on an existing Beamer login. Settings > Account lets you change your password, and there is no field there for changing your email.
To move yourself to a different address, replace the seat instead:
Go to Settings > Team.
Invite the new email address, with the role you want it to have.
Open the invitation from the new address and accept it.
Sign in with the new address and check you have the access you expect.
Go back to Settings > Team and remove the old address.
Do the steps in that order. Removing the old address before the new one is working leaves you locked out.
If your account signs in through Google or SAML SSO, this does not move your SSO identity across. See Your organisation changed email domain below.
On a Free account this route is not available. A Free account holds one team member, so the email on it cannot be changed and nobody can be invited. To move to a different address you either upgrade, or start a new account on the address you want.
The account's billing email
Invoice and billing contact details are not editable from the dashboard. Contact our support team with your Product ID and the address you want them sent to, and we will change it. See Find and manage your invoices.
An email address already tied to an account
An email address can only hold one Beamer account at a time. If you try to sign up with an address that already has an account, signup is refused and you will need a different address.
If you hit this, you probably already have an account you have lost track of. Common reasons:
You signed in with Google at some point, which created an account you did not intend to make.
A colleague set the account up and invited you, so the address is already a team member.
You created a trial account previously.
Before creating a new account on a different address, try a password reset on the original one. See Troubleshooting: I can't log in to Beamer.
We cannot release an address that already has an account, so a second account has to be created on a different address. That does not mean working in two places. One person can be a member of both accounts and move between them from their name in the bottom-left of the dashboard.
Your organisation changed email domain
If your company has moved from one email domain to another, the account email and the SSO identity behind it are two separate things, and moving one does not move the other. Left half-moved, sign-in fails.
Contact our support team and tell us:
The old address and the new address.
Which one should stay active.
That your organisation migrated domains.
We unlink the SSO identity from the address you are leaving and set up the one you are keeping. See also Troubleshooting: I can't log in to Beamer and Single sign-on (SAML SSO).