Rule updates
What changed, who it affects, and what it costs
Short, sourced explanations of important marketplace and carrier rule changes already reflected in the calculators.
- USPS dimensional weight changed July 12, 2026The divisor moved from 166 to 139. See which boxes are affected and a worked 12 lb versus 14 lb example.Read update →
- eBay performance surcharges changed July 1, 2026Long-running Below Standard and very high INAD ratings now trigger higher surcharges.Read update →