- Dolphin International - A quarterly printed magazine for penpals, marriages, and snail mail friends.
- Dovile's Snail Mail Pen Pals - Get tips on letter writing and improve your language skills by writing people all around the world.
- Global Penfriends - List your information for free for others to contact you, or join Global Penfriends to select your own penpals.
- International Pen Friends - Established in April 1967, membership has grown to over 1.5 million worldwide. Individual and school applications are available.
- Letters 4 Friends - Pen pals listed by country or date of addition. Available also in German and French.
- Maarten's Snail Mail Pen Pals - View penpals based on date submitted or by country, age, and gender.
- Pen Pallers Zone - A site with both email and postal penpals, swappers, and slam books.
- Penpals Cafè - A free snail mail penpal service.
- Peter's Penpal Club - Privately register for a free personalized penpal match.
- SAPE - Matches people with penpals in the former USSR and Baltic countries. Applications by snail mail only
- The Letter Exchange - A Magazine for Letter Writers - Anonymous pen pal listings in 35 categories like Daily Life, Literature, and Ghost Letters (writing as imaginary characters). Subscription includes confidential forwarding.
- The Mailbox - Adult only penpal listings for friends in a guestbook format by age group. Penpals must be contacted by email to request their postal address.
- WCF's International PenFriends - A non-profit cultural and educational organization based in the USA that has grown to over one million members in over 251 countries and territories around the globe.
