USPS flat rate shipping breaks from its usual price hike pattern in 2026. For the first time in years, some flat rate envelope prices will actually drop by up to $0.20, even as Priority Mail services overall increase by approximately 6.6%. The changes take effect January 18, 2026, creating a mix of price adjustments that makes some popular shipping options more affordable.
The Postal Service approved specific decreases alongside broader increases. Flat Rate Envelopes will drop by $0.20, while Padded and Legal Flat Rate Envelopes will decrease by $0.10 each. Most weight-based Priority Mail rates will increase by up to 13%. Priority Mail Express prices will rise by an average of 5.1%, and Ground Advantage services will see a 7.8% increase. First-Class Mail stamp prices remain unchanged for this price update. The Postal Service frames these targeted changes as part of its ongoing plan to restore long-term financial sustainability.
For anyone who hasn’t revisited the basics in a while: flat rate means you pay one price regardless of weight (up to 70 lbs) or distance. A Small Flat Rate Box shipped from Miami to Anchorage costs the same as one sent across town. That simplicity is the whole selling point. No scale, no zone chart, no surprises. You grab the free packaging from USPS, stuff it full, and the price is the price. USPS Flat Rate pricing is tied to the packaging type (Envelope vs. Box, Small vs. Medium vs. Large). That means the fastest way to overspend is picking a bigger Flat Rate container than you need, or using Flat Rate when a lightweight shipment would be cheaper by weight (especially nearby).
USPS announces 2026 flat rate price changes
The Postal Service officially filed for new shipping rates starting January 18, 2026. The USPS Board of Governors approved these adjustments to maintain competitiveness.
Flat rate customers face mostly increases across popular shipping options. The Flat Rate Envelope jumps to $11.95 from $11.00, while the Small Flat Rate Box rises to $12.65 from $11.70. The Medium Flat Rate Box increases to $22.95 from $21.05. Large Flat Rate Boxes will cost $31.50, up from $29.95. Military APO/FPO/DPO Large Flat Rate Boxes see a smaller increase to $30.15.
Commercial customers continue receiving discounted rates compared to retail prices. A Flat Rate Envelope costs $10.30 for businesses versus the $11.95 retail rate.
These adjustments align with broader shipping rate increases across USPS services. Priority Mail averages a 6.6% increase, Priority Mail Express rises 5.1%, and USPS Ground Advantage climbs 7.8%. Parcel Select prices rise approximately 6.0%.
First-Class Mail stamps remain unaffected with no price increase.
USPS adjusts flat rate box and envelope prices
Flat rate shipping packages face varied price adjustments starting January 18, 2026. These changes affect how frequent flat rate users plan their shipping costs across different package types.
Priority Flat Rate Envelopes Increase by $1
Before the new pricing, a quick refresher on what fits where: the standard Flat Rate Envelope measures 12½” x 9½” and works for thin items like documents, contracts, photos, and soft goods like t-shirts. The Legal Flat Rate Envelope runs 15″ x 9½”, giving you extra room for legal-size documents and oversized paperwork. The Padded Flat Rate Envelope (12½” x 9½”) adds built-in cushioning for small electronics, jewelry, or anything that needs a little protection in transit. The Window Flat Rate Envelope continues serving pre-addressed mailings. All four must close and seal completely… no bulging, no tape-assisted miracles. If it doesn’t close cleanly, you need a box.
Across the board, Flat Rate Envelope pricing increased by about $1 for all products. Flat Rate Envelopes now cost $11.95 at post offices, up from $11.00. Legal Flat Rate Envelopes increase to $12.25, and Padded Flat Rate Envelopes jump to $12.95. Commercial customers pay substantially less, with standard envelopes at $10.30, legal envelopes at $10.80, and padded options at $11.10.
Priority Mail Flat Rate Envelopes — 2025 vs. 2026 Retail Prices
| Packaging Type | 2025 Price | 2026 Price | Change |
|---|---|---|---|
| Flat Rate Envelope | $11.00 | $11.95 | +$0.95 |
| Legal Flat Rate Envelope | $11.20 | $12.25 | +$1.05 |
| Padded Flat Rate Envelope | $11.95 | $12.95 | +$1.00 |
Priority Flat Rate Boxes Increase by $1-2
Small Flat Rate Boxes now cost $12.65 at retail locations, up from $11.70. Medium Flat Rate Boxes see a larger jump to $22.95 (previously $21.05), regardless of whether customers choose the top-loading or side-loading version.
Large Flat Rate Boxes reach $31.50 (up from $29.95), though military APO/FPO/DPO shipments receive a discounted rate of $30.15. Business customers benefit from significant savings across all box sizes, with commercial prices set at $11.20 for small, $19.60 for medium, and $28.70 for large boxes.
| Packaging Type | 2025 Price | 2026 Price | Change |
|---|---|---|---|
| Small Flat Rate Box | $11.70 | $12.65 | +$0.95 |
| Medium Flat Rate Box | $21.05 | $22.95 | +$1.90 |
| Large Flat Rate Box | $29.95 | $31.50 | +$1.55 |
| APO/FPO/DPO Large Flat Rate Box | $28.70 | $30.15 | +$1.45 |
Here’s the size breakdown worth bookmarking: the Small Flat Rate Box (8⅝” x 5⅜” x 1⅝”) is ideal for small, dense items like phone accessories, cosmetics, or small tools/hardware. The Medium Flat Rate Box comes in two versions: a top-loading option (11¼” x 8¾” x 6″) and a side-loading version (14″ x 12″ x 3½”) that’s perfect for books, framed prints, subscription kits or flat merchandise. The Large Flat Rate Box (12¼” x 12¼” x 6″) are the “ship a lot, ship it once” workhorse when you’re packing multiple items securely.
All flat rate products maintain their key advantage, shipping packages up to 70 lbs anywhere in the US for one predictable price.
Priority Mail Express Decreases Overnight Pricing
Priority Mail Express flat rate services will see price decreases in 2026, a rare occurrence in postal pricing, but only if you have access to commercial rates. This marks a notable exception to the overall trend of postal rate hikes as the USPS fights off FedEx and UPS.
Priority Mail Express for ordinary people as a whole will see an average increase of 5.1% despite these commercial decreases. The 2026 retail price for a standard flat rate envelope will be $33.25, while commercial customers will pay just $28.80. The legal flat rate envelope will cost $33.50 retail but only $29.10 for commercial shippers. Given the significant savings, it’s worth noting: Any business using a USPS-compatible shipping platform (Stamps.com, ShipStation, or similar services) automatically qualifies for commercial rates. You don’t need a special contract or minimum volume.
| Packaging Type | 2025 Retail Price | 2026 Retail Price | 2026 Commercial Price | Change |
|---|---|---|---|---|
| Express Flat Rate Envelope | $31.40 | $33.25 | $28.80 | +$1.85 |
| Express Legal Flat Rate Envelope | $31.65 | $33.50 | $29.10 | +$1.85 |
| Express Padded Flat Rate Envelope | $32.25 | $34.15 | $29.35 | +$1.90 |
These adjustments reflect USPS’s strategic pricing approach. Priority Mail Express remains the premier overnight service for businesses, delivering in 1-3 days with a money-back guarantee. For time-sensitive documents and packages weighing up to 70 pounds, these services offer predictable flat rate pricing regardless of destination within the US.
Looking ahead: Mixed price adjustments reflect USPS strategy
The 2026 flat rate changes mark a departure from the usual pattern of across-the-board increases. Flat rate envelope decreases provide genuine savings for frequent shippers, while box prices continue climbing. This mixed approach reflects the Postal Service’s effort to balance competitive positioning with financial necessity.
Commercial shippers benefit significantly from the pricing structure, paying substantially less than retail customers across all flat rate products. The core advantage of flat rate shipping remains intact—predictable pricing for packages up to 70 pounds regardless of destination.
Ultimately, the Postal Service is trying to balance market competition with operational sustainability. The selective price decreases on envelopes suggest strategic positioning, while box increases reflect continued cost pressures. Flat rate loyalists face a more complex pricing landscape but retain the predictable shipping costs that make these services attractive for businesses and individuals nationwide.
All of these pricing increases go into effect January 18, 2026.
