The details, side by side
Your next letter.
Your shortlist.
A starting comparison of PieterPost, Mailform, and LetterStream. Choose up to three services from the directory to make your own.
Back to all services| What matters |  PieterPost |  Mailform |  LetterStream |
|---|---|---|---|
| Best fit | One-off US letters & Certified Mail | US PDFs & mailing options | US business & Certified Mail |
| Recipient markets in this directory | USA | USA | USA |
| One-off setup | No account needed | Guest checkout | Free account |
| Pricing approach | Pay per letter | Pay per mailing | Usage-based |
| Guest checkout | Advertised | Advertised | Not confirmed in this profile |
| US Certified Mail | Advertised | Advertised | Advertised |
| Mail API | Advertised | Not documented in this profile | Advertised |
| Source check | 20 October 2026 | 14 October 2026 | 14 October 2026 |
| Official website | Visit website | Visit website | Visit website |
“Not documented” is not a claim that a feature is unavailable. Read the source-linked profiles and confirm the current order options.