Stamps and Surcharges for Non-machineable Mail
When mailpieces don't fit the standard flat rectangular shape, the United States Post Office considers the letter "non-machineable" and imposes a surcharge. Examples of letters the USPS deems as odd-sized/nonmachineable include:
- square envelopes
- envelopes that are too rigid
- envelopes that don't bend easily
- envelopes that have clasps, strings, or other non-standard closures
Wedding invitations considered "odd-size" or "nonmachineable" will be subject to a $0.46 surcharge (current rate in 2024). This is an additional fee to the base rate for 1st-class mail by weight. Confused? Our postage calculator will help you determine the postage rate you need.
It is easy to use one of the non-machineable postage stamps below which includes both the standard rate for a 1oz letter as well as the additional non-machineable surcharge. However, some couples don't like the look of the butterfly stamp on their odd-sized invitations. Thankfully you don't have to use non-machineable postage stamps to send your non-machineable letters. Alternatively, you can use other postage stamps (including multiple stamps) on a letter as long as the postage adds up to enough to cover the current base rate (based on the weight of your letter) plus the current non-machineable surcharge.
The current USPS rate for non-machineable postage stamps is $1.19 ($0.73 for a one ounce letter + the $0.46 non-machineable surcharge). Like forever stamps, these stamps will always be equal to the current rate required to send a non-machineable 1 oz letter no matter when they were purchased. You can find their selection of non-machineable stamps below:
Colorado Hairstreak
FREE 2-Day shipping & FREE returns with Prime
Delivery: 5-7 days; No returns; Lowest prices
Issued in 2022 this non-machineable surcharge stamp features a Colorado Hairstreak. Available at your local post office.
California Dogface
FREE 2-Day shipping & FREE returns with Prime
Delivery: 5-7 days; No returns; Lowest prices
Not available at your local post office. Online only. Issued in 2019 this non-machineable surcharge stamp features a California Dogface butterfly.
Eastern Tailed-Blue
FREE shipping & FREE returns with Prime
Delivery: 5-7 days; No returns; Lowest prices
Issued in 2016 this non-machineable surcharge stamp features a Eastern Tailed-Blue butterfly.
Not available at any post office.
2024 Rates for Odd-sized Letters that Weigh More Than One Ounce
While rare, occasionally a letter needs to be mailed that is over one ounce in weight AND odd-sized (which the USPS calls non-machineable). In these instances, the amount of postage needed to send the letter is the base rate for the weight of the letter plus the current additional surcharge. Below is a table showing the cost of postage needed to send letters of such weights and sizes.
| Non-machineable Mailpiece | Base Rate for Weight | Non-Machineable Surcharge | Total Postage Required |
|---|---|---|---|
| 1 oz - odd size letter | $0.73 | $0.46 | $1.19 |
| 2 oz - odd size letter | $1.01 | $0.46 | $1.47 |
| 3 oz - odd size letter | $1.29 | $0.46 | $1.75 |
Remember, you must have enough postage on a letter, but you can have more than is needed. This means you can use multiple stamps on a letter so long as they add up to the amount of postage required to deliver it.