I also use Mullvad and I pay by sending an anonymous envelope of cash to Sweden with a random number scribbled on a bit of paper. So far all of the cash I’ve sent has been added to my accounts. There’s obviously no way to know whether they follow through on their no-log claim but my sense is they’re pretty trustworthy. At the very least the person who opens their mail is.

I can't tell if this is real or not. Do you actually send cash to Sweden?

I do indeed! I’ve sent USD, GBP, and Euros from all over the world - Europe, North Africa, South America, and the US. (I was a “digital nomad” pre-pandemic.) They even give you a one-time-use token for cash payments so you can maintain the anonymity of your account number if the letter is intercepted.

Other than the letter I sent from Morocco, I never included a return address.

That is one of they many ways in which you can add money to a Mullvad account. You should try creating an account; it only takes one click.

I just signed up with Surfshark but I'll definitely check out Mullvad.

When he says it's just one click to generate an account, he means it.

https://mullvad.net/en/account/create/

That link automatically creates a new account. No names, no email address (except if you set up a PayPal subscription), not even a password. Your account number is literally all you need. They even have a FAQ that provides a generalized database schema.

https://mullvad.net/en/help/no-logging-data-policy/#numbered

It is possible (and yes, I tried it!), although other payment methods are available, including some more conventional methods.

Mullvad also happens to be Firefox's choice of vpn provider.

Why not just use Bitcoin or gift card?

Not the person you're responding to, but bitcoin isn't that anonymous. Much more than a credit card, but less so than cash.

Bitcoin ATM/local bitcoin -> sell for monero/mixer -> buy monero.