By clicking "options", and then "purchase gift certificate", you can send gift certificates to FastMail users, which they can use to upgrade their account. However, previously recipients had to already be FastMail users in order to use the certificate.
We have just added new functionality which allows recipients of gift certificates to use the certificate to sign up a new, upgraded account. This will be particularly useful to small/medium businesses and families, or anyone else with a number of accounts under their own domain. To create accounts for everybody in your business or family under your own domain, firstly follow these instructions to create your domain. Then, send yourself a gift certificate for each account which you require for your colleagues or family members, and then follow the instructions in each gift certificate to use it to create a new account. If you need any help in setting up your business or family, please click here to request support.