Sendpaper vs. Mailform
Mailform is a full mailroom on the web. Sendpaper is quick and agentic: mail sent by your AI agent.
Short answer
Mailing long documents, overnight by FedEx, abroad, or in bulk from your office? Use Mailform.
Want your AI agent to write and send a letter, a certified letter or a few postcards, with a person checking it before it prints? Use Sendpaper.
Side by side
| Feature | Mailform | Sendpaper |
|---|---|---|
| Built for | Offices mailing documents: invoices, legal and medical paperwork, bulk mailings | Quick, agentic mail: your AI agent drafts it, you approve it, it's sent |
| Getting started | One letter needs no sign-up; bulk, credits and the API need an account | No account for anything: web, API, agent or up to 25 recipients |
| How you pay | Per order by card, Link or PayPal, or prepaid credits; optional monthly plans | Per order: card checkout, or your agent pays with Stripe Link once you approve |
| AI agents | No official MCP server; a Microsoft connector for Copilot Studio | Built-in MCP server for Claude, Codex, Muse and any MCP client. No key needed |
| Developers | REST API with keys, test mode and webhooks | REST API and MCP, no keys |
| Formats | PDF or Word, long documents, 4×6 postcards, checks, return envelopes | Letters from text or a PDF up to 6 pages, postcards in 4×6, 6×9 and 6×11 |
| Certified mail | Certified, with an electronic or green-card return receipt | Certified letters, with an optional return receipt |
| Speed | First-Class, Priority, Priority Express, FedEx and UPS overnight | First-Class, or Express by USPS Priority |
| Review before printing | Mostly automated; we found no content review before printing | A real person checks every piece before it prints |
| Where it mails | US and international | US only, including territories and military addresses |
| Printing partner | Lob, through the Lob API | PostGrid |
| Trustpilot rating | 1.6 out of 5 from 22 reviews (October 2026) | No reviews yet |
Which fits
When to choose Mailform
Mailform is the better choice when mail is office work: a 40-page contract, an invoice run, a document that has to arrive the next business day by FedEx, or a letter abroad. For short letters, certified letters and 4×6 postcards, its prices are lower than ours, and it covers more ground, with Word uploads, green-card return receipts, checks, return envelopes and bulk mail from a spreadsheet.
It also suits teams that want shared accounts, mailing lists and a developer API with test keys and webhooks, and for one letter from the website you don't even need to sign up.
When to choose Sendpaper
Sendpaper is the better choice when an AI agent is doing the work. Claude, Codex, Muse or any MCP client connects to our server with no key, drafts the letter or postcard with you, and you approve the payment. No account, no API key and no prepaid credits, even through the API or for up to 25 recipients at once. Here's how to connect Claude.
It also fits mail where the wording matters: a certified letter to a landlord or a creditor, a note an agent wrote for you, or a PDF you already have. A real person looks at every piece before it prints, and you get larger postcards, up to 6×11. Not sure you need certified? Read what certified mail proves.
Common questions
Is Sendpaper built on Mailform?
No. Sendpaper's printing and mailing partner is PostGrid. We don't use Mailform.
Is Mailform cheaper?
For short mail, yes: a letter of a few pages, a certified letter and a 4×6 postcard all cost less at Mailform (see Mailform's pricing). Mailform charges for each extra page, so a PDF near our six-page limit can cost about the same at both. Sendpaper adds a first-party agent connection, no account for API or group sends, and a person reviewing every piece.
Can an AI agent send mail through Mailform?
Not through an MCP server. We found no Mailform MCP server, ChatGPT app or Claude connector on its site, its GitHub, the official MCP Registry, Smithery or Glama as of October 11, 2026. Mailform does publish a Microsoft connector for Power Automate and Copilot Studio, which needs an account with prepaid credit, and a developer could build their own integration with Mailform's API, which needs an account and an API key.
Do I need an account for Mailform?
Not for a single letter or postcard from its website. You do for bulk mail, prepaid credits and the API.
Sources
16 links
- Mailform: pricing
- Mailform: FAQ (services, turnaround, payment, mails through Lob)
- Mailform: homepage (no sign-up for single letters and postcards)
- Mailform: API documentation
- Mailform help: tracking, return receipts and Priority signatures
- Mailform help: return receipt options
- Mailform help: uploading Word documents
- Mailform help: long documents
- Mailform help: how orders are fulfilled (mostly automated)
- Microsoft: Mailform connector (Power Automate, Copilot Studio)
- Trustpilot: Mailform reviews (1.6 from 22, checked October 12, 2026)
- Mailform: terms of service (content rules)
- Mailform: privacy policy
- Official MCP registry (no Mailform server found)
- Sendpaper pricing
- Sendpaper content policy
Mailform sources accessed October 12, 2026. We're not affiliated with Mailform; our printing partner is PostGrid.