Guerrilla Mail alternative: GrabMail vs Guerrilla Mail

At a glance

Fourteen rows. Every Guerrilla Mail cell is what its home page, about page, API document and terms said on 2 September 2026; every GrabMail cell is read from the constants the service enforces. “Partly” means a paid tier or a caveat the row cannot hold — the sections below say which.

Checked 2 September 2026. Guerrilla Mail’s API document is dated 19 April 2011 and states that its rate limits exist but are not published; the site’s Compose feature was showing “Sending email has been suspended for today” at the time of checking. Where a figure is not published, the cell says so.

What Guerrilla Mail does well

Guerrilla Mail has been the free, keyless option since before most of this category existed. Four things it does that GrabMail does not:

• Eleven domains. sharklasers.com, grr.la, pokemail.net, spam4.me and seven more. When a sign-up form refuses one, the next is a click away. GrabMail has 8 public domains and a paid pool for the forms that refuse all of them.
• A private custom domain for $9.99 a year. Point a domain you own at Guerrilla Mail and mail to it is “accessible only by you”, or opened to everyone if you prefer. GrabMail’s free domain is a catch-all inbox anyone who knows an address can read.
• A mail server you can run. Go-Guerrilla, the open-source MTA behind the service, is on GitHub. Nothing of GrabMail is published as code.
• Sending, sometimes. The Compose tab can send from a temporary address — with your IP in the headers, and suspended on the day these facts were checked. GrabMail cannot send at all, by design.

Where GrabMail is different

GrabMail keeps what makes Guerrilla Mail good — free, keyless, any address — and changes the four things that make it hard to build on.

• 5 days, not one hour. A Guerrilla Mail message is gone in sixty minutes, two hours if you extend it twice. A GrabMail message stays 5 days on the public domains and on yours, which is long enough for a trial that emails on day three and for a test that runs overnight.
• A stateless API with a published limit. Guerrilla Mail’s API carries state in a session cookie that expires after about eighteen minutes idle, and its rate limits are deliberately unpublished. GrabMail’s is a GET with the address in it, no session, and one read a second per address written down on the limits page.
• No ads and an MCP server. No AdSense, no Analytics, no third-party script on any page. And an MCP server at https://grabmail.io/mcp that lets an agent open an inbox and block on wait_for_message for up to 25 seconds — Guerrilla Mail has nothing for agents.
• Your own domain for nothing. One MX record at smtp.grabmail.io and every address on the domain is a catch-all inbox, no yearly fee, no payment step. It is public, where Guerrilla Mail’s paid one can be private; the row above says so.

Price, side by side

Guerrilla Mail sells one thing, a custom domain by the year, and publishes no refund terms. GrabMail’s only paid plan buys access to a pool of domains kept off the disposable-mail blocklists; everything in the table above stays free.

Prices as published on 2 September 2026. GrabMail’s pricing page has the full grid.

For developers: reading a mailbox

The whole difference in one command. This reads a GrabMail mailbox with no header, no key, no account and no session:

$ curl -sG https://grabmail.io/api/v1/mailbox --data-urlencode "address=anything@grabmail.io" | jq '{count, alias}'

The Guerrilla Mail equivalent is two calls: get_email_address to open a session and get a cookie, then check_email with that cookie and a sequence number, twenty messages a page. It has worked since 2011 and the site’s own front end runs on it. The difference is the session: a test that forgets the cookie, or waits eighteen minutes, starts over. GrabMail’s reference is three stateless endpoints; the Python and Node.js guides have the wait loop.

One habit carries over exactly: on both, an address is a name you typed, so a suite that builds run-{id}@ addresses works unchanged. Watch the retention when you move: an hour is enough for a code, and not enough for a job that retries in the morning.

For AI agents

Guerrilla Mail publishes nothing for agents — no MCP server, no llms.txt — though its keyless API can be called by one that manages the session cookie. GrabMail’s server at https://grabmail.io/mcp gives an agent an inbox with no key: create_inbox, a blocking wait_for_message of up to 25 seconds, read_message.

Email for AI agents covers the four-call loop and the guard rails; the client guide has the configuration for Claude, Cursor and five others.

Switching from Guerrilla Mail

Both are keyless, so the switch is short:

1. Keep your naming, change the domain. name@sharklasers.com becomes name@grabmail.io, or any name on a domain of yours with its MX at smtp.grabmail.io.
2. Drop the session. Replace get_email_address plus check_email with a GET on /api/v1/mailbox?address=…; there is no cookie to carry and no sequence number. Page with the next cursor if a mailbox is busy.
3. Remove the extend calls. Nothing here needs extending: 5 days is the window, for every message.
4. Decide about privacy. If you paid for a private custom domain, know that the same domain here is public; hand out the alias where privacy matters, or stay.

Which one, for what

The honest split:

When to stay with Guerrilla Mail

Three situations where switching would cost you something real:

• Your custom domain is private and you rely on that. Guerrilla Mail lets you make it “accessible only by you”; GrabMail does not, at any price. That is a real difference, not a footnote.
• You rotate domains to get past blocklists. Eleven public domains beat 8. GrabMail’s answer is a paid pool of off-blocklist domains or a domain of your own; if you would rather not do either, stay.
• You need to send. Even suspended some days, Guerrilla Mail’s Compose exists; GrabMail has no sending path and will not add one.

Questions