Mailing a whole client list without a mail-merge headache
By Justin Winter · Updated August 22, 2026
Property managers, consultants, and small firms who mail the same notice to many people at once can upload a spreadsheet — name, address, city, state, ZIP — and paperplane sends every row its own individually addressed letter for $1.99 First-Class each. It's one shared letter to a list of real addresses, not a marketing campaign platform.
If you manage mail on behalf of other people — a property manager notifying tenants, a consultant sending the same document to a roster of clients, an HOA board mailing all its owners — the usual options are bad: stuff envelopes by hand, wrestle a mail-merge template into a Word document and a printer, or sign up for an enterprise mailing platform built for marketing campaigns you don't need. paperplane's spreadsheet upload is built for the case in between: a real list of individual mailing addresses that all need the same letter, sent as actual USPS mail.
What actually happens when you upload a list
From the send page, switch to bulk mode and drop in a CSV or TSV export from whatever you already use to track clients or tenants — spreadsheet, property management tool, CRM export, it doesn't matter. paperplane reads the header row, matches your columns to name and address fields automatically (it recognizes headers like "Tenant Name," "Property Address," or "Resident" without you renaming anything), and shows you every row with its status before anything is sent — ready, worth a check (a ZIP we had to repair, a state we guessed from "Calif."), or can't send (a missing city, an address we can't place). You fix what needs fixing in your own spreadsheet or by hand, then confirm.
Once confirmed, each row becomes its own order against the same system a single letter goes through — its own PDF, its own envelope, its own USPS postage. There is no batch-level record beyond the list of order confirmations you get back at the end; each letter is tracked individually, the same as if you'd placed it on its own.
Individual letters at scale, not a mail campaign
This distinction matters because it's easy to assume "upload a list" means something bigger than it is. It doesn't. Every row you upload becomes one letter to one address — there is no bulk discount pricing tier, no send scheduling, no A/B testing, no unsubscribe management, and no postcards. You are not setting up a campaign; you are placing many individual First-Class orders in one pass instead of one at a time. That's a meaningfully different (and much simpler) thing than the marketing mail platforms built for prospecting lists, and it's priced the same way: $1.99 per letter, whether you send one or a thousand.
| Situation | Fits the spreadsheet upload? |
|---|---|
| Notify 40 tenants of a rent increase, same letter to each | Yes — one upload, 40 individual First-Class letters. |
| Send an annual disclosure to every client on file | Yes — same text, list of addresses. |
| Mail each client a different invoice amount or personalized paragraph | No — every row gets identical letter text today; send those individually. |
| Serve formal notice to one tenant with proof of delivery required | No — Certified Mail ($12.99–$14.99) is sent as a single order, not through bulk upload. |
| Recurring monthly mailing to the same list on a schedule | No — there's no scheduling; each batch is a manual upload and send. |
Pricing — the same rate whether it's one letter or many
| Service | Price per letter | Available via spreadsheet upload? |
|---|---|---|
| First-Class | $1.99 | Yes |
| Certified Mail | $12.99 | No — send individually |
| Certified + electronic Return Receipt | $14.99 | No — send individually |
| Priority Mail | $24.99 | No — send individually |
There's no subscription and no per-seat fee for managing the list — you pay per letter, the same $1.99 First-Class rate as a single send. In sandbox mode you can run a whole list through for free to see exactly how it will look before a single real letter goes out; live mode creates a real, payable order for every recipient.
What we don't keep track of for you
To be direct about the limits: paperplane doesn't currently give you a running dashboard of everyone you've ever mailed, or a client roster that remembers addresses between visits — each upload is its own pass, and each order is tracked individually by its own order confirmation. If you need a persistent record of who you mailed and when across many separate sends, keep your source spreadsheet as the record and re-upload it (or an updated version) whenever the next mailing goes out.
Related: if a specific letter in your list needs certified proof of delivery rather than a plain First-Class send, see what Certified Mail is and legal mailing services for notices where proof matters.
Common questions
Is this a mail-merge tool, a CRM, or a marketing campaign platform?
None of those. You upload a CSV or TSV of names and addresses, write one letter, and paperplane creates one individually addressed order per row — the same way you’d place each order by hand, just without typing every address in yourself. There is no template personalization beyond the address block, no scheduling, no recurring sends, and no analytics dashboard. If you need true mail-merge (a different paragraph per recipient) or a CRM to track relationships over time, this is not that product.
Can I bulk-send Certified Mail to my whole list at once?
Not today. The spreadsheet-upload flow creates First-Class letters at $1.99 each. If a specific letter — a lease violation notice, a formal client notice — needs Certified Mail's proof of delivery ($12.99) or Certified with electronic Return Receipt ($14.99), send that one individually through the regular send flow. For a batch where every recipient needs certified proof, you'd currently place those as separate individual orders rather than one bulk run.
How big a list can I upload, and does my client list get stored?
Up to 5,000 rows in a CSV or TSV file, 5MB max, columns in any order — we match "Property Address," "Tenant Name," "Resident," and similar variants automatically. Only the header row and three sample rows are sent to our server to help match your columns; the rest of your list is read and processed in your browser and only becomes real orders when you confirm and send.
Does every recipient get the exact same letter?
Yes — the text you write is what every address in the batch receives. That fits a rent increase notice, a policy update, an annual disclosure, or any letter where the wording is identical and only the recipient changes. It does not fit a letter that needs a different name, balance, or paragraph per person; that still has to be sent as individual orders today.