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Wedding Math

Day-of logistics calculator

Wedding Invitation & Postage Calculator

Turn your guest list into a realistic stationery order: how many invitations, save-the-dates, and thank-you cards to buy, your total postage, and when to mail each piece. Lock in your headcount first with the guest list calculator.

Your details

Households = guests ÷ this

Your invitation plan

Invitations to order
83
Households
75
Postage
$234

Mailing timeline

Mail save-the-dates (~6 months out)
December 12, 2026
Mail invitations (~8 weeks out)
April 17, 2027
RSVP deadline (~4 weeks out)
May 15, 2027
Give caterer final count (~2 weeks out)
May 29, 2027
  • You'll mail about 75 invitations (one per household), ordering 83 to cover keepsakes and mistakes.
  • Order envelopes and invitations together, and buy a few extra outer envelopes for addressing errors.
  • Take a fully assembled invitation to the post office to weigh it — square or chunky invites need extra postage.
  • Save-the-dates can go on cheaper postcard postage to save money.

This is an estimate, not a guarantee. Wedding costs and quantities vary by region, season, and vendor — verify before you buy or sign.

How this is calculated

  • Invitations are counted by household = guests ÷ average guests per invitation (default 2).
  • Order ~10% extra for keepsakes and addressing mistakes.
  • Postage covers an outgoing stamp (double for heavy/square), a reply-card stamp, save-the-dates, and thank-yous.
  • Mailing timeline: save-the-dates ~6 months out, invitations ~8 weeks out, RSVP ~4 weeks out.

Every figure here is a well-worn planning rule of thumb, not a quote — use it to budget early, then lock in real numbers as you book.

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Frequently asked questions

How many invitations should I order?

Order one invitation per household, not per guest, then add a buffer. This calculator divides your guest count by the average guests per invitation to get households, and adds your chosen extra percentage (10% by default) to cover keepsakes and addressing mistakes.

How much postage will I need?

The estimate totals stamps for outgoing invitations, reply cards, save-the-dates, and thank-you cards at your stamp price. Square or heavy invitations need extra postage — toggle that option and the calculator roughly doubles the outgoing stamp.

When should I mail everything?

With a wedding date entered, you'll get a timeline: save-the-dates about six months out, invitations around eight weeks out, an RSVP deadline near four weeks out, and the final caterer count about two weeks out.

Why weigh an invitation before buying stamps?

Postage depends on weight and shape. A fully assembled invitation with inserts and a reply envelope can tip over one ounce or count as a square mailpiece, both of which cost more. Take a complete invitation to the post office to confirm the exact postage.

Last reviewed June 2026 by Jared Waterworth. Estimates use widely accepted wedding-planning rules of thumb — see how we estimate. Numbers vary by region, season, and vendor, so verify before you book or buy.