- Wedding Invitation Postage 2026: How Many Stamps You Need (With Examples)
2026 wedding invitation postage: how many stamps, typical costs (1 oz $0.78, 2 oz $1.07, square +$0.49), RSVP mistakes to avoid, and totals for 50–150 invites. Use the free calculator.
- 9×12 envelope postage explained
Why many 9×12 envelopes price as USPS large envelopes (flats), not letters: length limits, flat retail totals, stamp coverage, and links to calculators.
- Manila envelope postage mistakes to avoid
Common manila envelope postage mistakes: letter vs flat, clasps and rigidity, stamp math, and when to use large-envelope retail instead of letter stamps.
- USPS letter vs flat vs parcel (what this site covers)
How USPS First-Class letters, large envelopes (flats), and non-flat parcels differ for retail postage—and what this site’s calculators actually price.
- Additional-ounce stamps and USPS letters (what flats do differently)
How USPS additional-ounce postage fits First-Class letters, why flat mail uses a different table, and how to pair stamps without underpaying.
- Common USPS postage mistakes (and how to avoid them)
Practical checklist: weighing mail, letter vs flat, square surcharges, wedding reply postage, and links to calculators—avoid insufficient postage.