Guide
How to mail a demand letter (and keep proof)
If you are sending a demand letter, the goal is clarity and documentation. This guide covers how to package the letter, keep copies, and choose the right mail option.
Published Jan 20, 2026
How it works
Finalize the letter
Keep it factual and professional.
Add attachments
Invoice, contract, or timeline (if relevant).
Create a single PDF
Put the letter first, then attachments.
Choose delivery options
First Class or Express, plus Certified Mail (First Class only) if you need proof.
Mail it
We print and mail the packet through the appropriate mailing provider.
Keep proof of delivery
If proof matters, use Certified Mail with electronic return receipt (First Class only). It provides USPS tracking and a digital delivery record.
Certified Mail with electronic return receipt (First Class only)
Common mistakes to avoid
- Missing invoice numbers or amounts.
- No clear deadline date.
- Unclear payment instructions.
- Sending separate files instead of one PDF packet.
What you get
- • Demand letters mailed from a PDF
- • Certified Mail with electronic return receipt (First Class only)
- • First Class or Express delivery options
Which mailing option and proof should you choose?
PostalForm offers U.S. letter mailing with different delivery and proof options. First-Class suits routine correspondence; Certified Mail adds mailing and delivery records, and Electronic Return Receipt adds a downloadable signature record. Expedited delivery prioritizes speed. Review the destination, estimated dates, total price, and required proof before paying.
| Mailing option | Delivery speed | Proof | Use when | Avoid when |
|---|---|---|---|---|
| USPS First-Class Mail | First-Class Mail delivery estimate shown before payment. | Available processing scans; no recipient signature or Certified Mail receipt. | Routine letters when a signed delivery record is unnecessary. | Your instructions require Certified Mail, a signature, or a deadline this estimate cannot meet. |
| Certified Mail | First-Class delivery speed; certification does not make delivery faster. | USPS mailing and delivery/attempt tracking; no Electronic Return Receipt unless added. | You need a recorded mailing and delivery or attempted-delivery status. | You need a downloadable signature record or faster delivery. |
| Certified Mail + Electronic Return Receipt | First-Class delivery speed; signature collection may require redelivery or pickup. | Certified Mail records plus a downloadable USPS signature record when available. | Your instructions call for Certified Mail with Return Receipt or you need the signature record. | Your recipient requires an original enclosure, personal service, or another submission method. |
| Expedited / Express with signature | Faster estimated delivery range shown at checkout; production cutoff and destination apply. | Carrier tracking and signature option; this is separate from Certified Mail and ERR. | Speed and signature matter and checkout offers the service for your destination. | A rule specifically requires Certified Mail or the displayed estimate misses your deadline. |
Availability and delivery estimates depend on the document and destination. Mailing proof does not establish that a recipient accepted a filing or that legal service requirements were met. Delivery estimates · Full pricing
FAQs
- Do you offer tracking?
- Yes. Add Certified Mail with electronic return receipt (First Class only).
- Can I mail from my phone?
- Yes. Upload a PDF from your phone and check out on mobile.
Ready to get started?
Upload your finalized PDF and we will handle printing and postal mailing.