Small parcelCost guide3 min read

U.S. Priority Mail Not Over 1 Lb, Zone 1: Weight-Based vs. Flat Rate Prices

From October 4, 2026, through January 17, 2027, weight-based U.S. Priority Mail postage for not over 1 lb in Zone 1 is lower than every listed Flat Rate box price at retail and commercial rates.

By BoslogShip ResearchReviewed by BoslogShip Editorial ReviewPublished
U.S. Priority Mail Not Over 1 Lb, Zone 1: Weight-Based vs. Flat Rate Prices cover visual

For U.S. Priority Mail not over 1 lb in Zone 1, published weight-based postage is lower than Small, Medium, and Large Flat Rate box postage in both price classes.

The lower published-postage option

Source[1]

For this U.S. Priority Mail profile—weight not over 1 lb and Zone 1—the weight-based price is lower than every listed Flat Rate box price in both the retail and commercial price classes.[1]

U.S. Priority Mail published postage and price differences for weight not over 1 lb in Zone 1, effective October 4, 2026, through January 17, 2027.[1]
Price classWeight-basedSmall Flat Rate BoxFlat Rate minus weight-basedMedium Flat Rate BoxesFlat Rate minus weight-basedLarge Flat Rate BoxesFlat Rate minus weight-based
Retail$11.50$14.65$3.15$25.80$14.30$36.10$24.60[1]
Commercial$9.44$12.95$3.51$22.02$12.58$32.75$23.31[1]

Each difference equals the applicable Flat Rate box amount minus the corresponding weight-based amount. At retail, the differences are $3.15 for Small, $14.30 for Medium, and $24.60 for Large. At commercial prices, they are $3.51, $12.58, and $23.31, respectively.[1]

What the comparison does not establish

Source[1]

The supplied U.S. USPS sample does not establish negotiated prices, cubic rates, extra fees, a prior price baseline, or delivery commitments. In both price classes, the Flat Rate box amounts are separately listed without inferring shipment eligibility.[1]

How to apply the result

  1. Confirm the packed shipment's weight bracket, destination zone, and applicable price class before using the comparison.
  2. When minimizing published postage, compare the weight-based option before selecting a Flat Rate box.
  3. Confirm that the packed shipment fits and qualifies before using any Flat Rate packaging.
  4. Evaluate any quoted fees or delivery requirements separately from this published-postage comparison.
  5. For a shipment outside the stated effective period, check the published prices applicable to that shipment before making the comparison.

Sources and evidence

1 source

Each source is tied to a visible claim in the article. Access dates show when BoslogShip last verified the cited page.

  1. [1]

    Official primary source · United States Postal Service

    Final U.S. USPS domestic parcel postage: retail and commercial sample

    Published September 18, 2026 · Accessed November 7, 2026

    • Supports: The final U.S. USPS domestic published-postage sample is effective from October 4, 2026, through January 17, 2027.

      Data as of 2026-10-04

    • Supports: For U.S. Priority Mail retail pricing from October 4, 2026, through January 17, 2027, published postage is $11.50 for weight not over 1 lb in Zone 1, versus $14.65, $25.80, and $36.10 for Small, Medium, and Large Flat Rate boxes, respectively.

      Data as of 2026-10-04

    • Supports: For U.S. Priority Mail commercial pricing from October 4, 2026, through January 17, 2027, published postage is $9.44 for weight not over 1 lb in Zone 1, versus $12.95, $22.02, and $32.75 for Small, Medium, and Large Flat Rate boxes, respectively.

      Data as of 2026-10-04

    • Supports: For the U.S. retail profile of Priority Mail not over 1 lb in Zone 1, weight-based published postage is $3.15 lower than the Small Flat Rate Box price.

      Data as of 2026-10-04

    • Supports: For the U.S. retail profile of Priority Mail not over 1 lb in Zone 1, weight-based published postage is $14.30 lower than the Medium Flat Rate Boxes price.

      Data as of 2026-10-04

    • Supports: For the U.S. retail profile of Priority Mail not over 1 lb in Zone 1, weight-based published postage is $24.60 lower than the Large Flat Rate Boxes price.

      Data as of 2026-10-04

    • Supports: For the U.S. commercial profile of Priority Mail not over 1 lb in Zone 1, weight-based published postage is $3.51 lower than the Small Flat Rate Box price.

      Data as of 2026-10-04

    • Supports: For the U.S. commercial profile of Priority Mail not over 1 lb in Zone 1, weight-based published postage is $12.58 lower than the Medium Flat Rate Boxes price.

      Data as of 2026-10-04

    • Supports: For the U.S. commercial profile of Priority Mail not over 1 lb in Zone 1, weight-based published postage is $23.31 lower than the Large Flat Rate Boxes price.

      Data as of 2026-10-04

    • Supports: The supplied U.S. USPS sample does not infer negotiated prices, cubic rates, extra fees, a prior price baseline, or delivery commitments.

      Data as of 2026-11-07

    • Supports: In the U.S. retail comparison, the Flat Rate box prices are separately listed and do not establish shipment eligibility.

      Data as of 2026-10-04

    • Supports: In the U.S. commercial comparison, the Flat Rate box prices are separately listed and do not establish shipment eligibility.

      Data as of 2026-10-04

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U.S. Priority Mail Not Over 1 Lb, Zone 1: Weight-Based vs. Flat Rate | BoslogShip