Maski vs Fastmail Masked Email: you have to move house to get the doorbell

Fastmail is a genuinely good mail host. It is fast, it has no ads, the people who run it have been in email standards work for years, and Masked Email is a well-built feature inside it.

It is also a mailbox. The entry plan is $5 a month on twelve-month billing, which buys you an inbox with 60 GB of storage, and the masking is something you get along with it. There is no free tier, only a thirty day trial.

So the real question is not which alias tool is better. It is whether you want to move your email.

Two different bets about your inbox

Fastmail’s bet is consolidation. Your mailbox, your calendar, your contacts, your domains and your masked addresses in one account, with one company, under one bill. When that fits, it fits very well, and the masking being native to the client is a real advantage that a forwarding service cannot match.

Maski’s bet is that you already have an inbox and you are not going to change it. Whatever you use now keeps working. Aliases forward into it, replies go out through Maski so your real address stays hidden, and nothing about your existing mail setup moves.

One of these asks for a migration and the other asks for an MX record. That is most of the difference.

What matters, side by side

Maski compared with Fastmail Masked Email on price, aliases included, custom domains, replying to a forwarded message, and sending a new message from the alias.
Compared on	Maski	Fastmail Masked Email
Price	Free, or $4.99 a month for Pro Buys the alias service itself. No mailbox or storage is bundled in. Pro is free for a year for the first 1,000 sign-ups.	$5 a month for Individual on 12-month billing, $60 for 12 months Buys a mailbox with 60 GB of storage, masking included. No free tier, only a 30-day trial. US store. Pricing — Fastmail Masked Email, opens in a new tab
Aliases included	10 on Free, 25 on Pro	A cap exists and Fastmail does not publish the number They state a cap exists and do not publish the number. They never claim unlimited. Account limits — Fastmail Masked Email, opens in a new tab
Custom domains	Yes, on Pro Bring your own domain. Maski can publish the DNS records for supported providers.	Yes, and a Masked Email address can be created on one Usable for Masked Email. None on Basic, 100 plus one per user on the others. Masked Email — Fastmail Masked Email, opens in a new tab Account limits — Fastmail Masked Email, opens in a new tab
Reply to a forwarded message	Yes, on Pro The alias stays in the From address. Your real address is never disclosed to the sender.	Yes, and the masked address is the default sender The masked address is the default sender on a reply. Masked Email — Fastmail Masked Email, opens in a new tab
Send a new message from the alias	Yes, on Pro You compose in your own mail client and address the message through Maski, so the alias is the sender.	Yes, from the sending-address menu From the sending-address menu. Masked Email — Fastmail Masked Email, opens in a new tab

Verified 11 September 2026. I re-check every figure on its source page, and this date only moves when the whole table has been checked again.

There is no free tier to test the idea on

Every Fastmail plan offers a thirty day trial. A trial is not a tier. At the end of it you are either paying or you are migrating your mail back out, and any address you handed out during the trial is a problem you now own.

Masking is the sort of thing you want to try on two or three real signups over a couple of months before you commit to it. A trial clock is a bad fit for that, because the whole point of an alias is that it is still working a year later.

They will not tell you the limit

Fastmail is unusual in this field for being upfront that a cap exists. Their account limits page states there are limits on the total number of Masked Email addresses, and on how many you can create in a given period.

They do not publish the number. I respect the honesty of saying a limit exists rather than printing unlimited and hiding a footnote, which is more than some of this industry manages. It still means you cannot plan around it.

Worth knowing: Fastmail has a separate alias feature with separate limits. Masked Email and aliases are different things in different settings screens, and the big numbers you will find quoted online usually belong to the other one.

What you keep by not moving

Your address book. Your filters. Fifteen years of archived mail. Whatever your employer or your household already uses. The muscle memory of a client you have used every day for a decade.

None of that is a feature I built. It is just what you do not have to spend a weekend on, and it is the honest reason most people pick a forwarding service over a mail host.

BE HONEST: when Fastmail Masked Email is the right call

If you want a mailbox anyway, it is better value. Paying Fastmail $5 a month for an inbox with masking built in beats paying a mail host and then paying me $4.99 a month on top of it. Pro is free for a year for the first 1,000 sign-ups, which defers that arithmetic rather than winning it.

Masking inside the client is smoother. Generating a masked address from the compose window of the mail app you are already in beats any forwarding service on friction, and replying from one is the default rather than a feature you enable.

Their custom domain support is deeper. Custom domains work as the domain for Masked Email addresses, and their account limits page states 100 plus one per user on the plans that include them. That is a lot more headroom than Maski offers.

One hop instead of two. Mail to a Masked Email address lands in the same system that hosts your mailbox. Anything forwarded, Maski included, adds a relay between the sender and your inbox, and fewer moving parts is a real argument in email.

Is one of those the reason you would not switch?

Then tell me which one. If the thing keeping you on Fastmail Masked Email is a feature I do not have yet, I would rather hear it from you than guess at it, and a short note saying what you need and what you are using it for is worth more to me than any amount of competitor research.

Write to jay@maski.dev and it comes to me. If you would rather it went to the support queue, use hey@maski.dev. I cannot promise to build everything, and I will not pretend otherwise, but nothing gets built that nobody asked for.

Keep your inbox. Add the aliases.

If you were not otherwise shopping for a mailbox, you do not need to move to get masked addresses. Point an alias at the inbox you already use and see whether that is enough. The free plan does not need a card.

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