What postage amount do I need?

From Save the Date cards to Bridal Shower invitations, Wedding Invitations, RSVPs and Thank You Notes, bridal mailing comes in many different shapes, sizes and weights. To make sure you don't over-spend on postage, here are a few simple guidelines to follow:

1. First consider size and thickness

Letter - Letter envelopes typically have dimensions between 5" and 11.5" long, 3.5" and 6.125" high and 0.007" and 0.25" thick.

Note: Letters are subject to a $0.15 surcharge if they are 1.) Square 2.) Rigid 3.) Or have certain non-machinable characteristics.


Flats - Flats are large envelopes, cost more than letters and typically have dimensions between 11.5" and 15" long, 6.125" and 12" high, and 0.25" and 0.75" thick.

2. Now consider the weight

Weight is very important to determine the correct postage amount.

Weigh it twice, send it once.

Accuracy is everything when sending your wedding mail. Make sure you weigh your mail on a scale that is precise to 0.1 oz. Common kitchen scales, a scale at the post office, or a Stamps.com postage scale (Click to purchase) is your best bet. Bathroom scale or guessing the weight are not wise options. No one wants to guess their way into a load of returned wedding invitations.

Save money by using postcards for RSVP and Save the Dates

Postcards are $0.35 while a letter is $0.55. Save $0.20 per mailpiece by making your RSVP and Save the Date cards in postcard form.