Shipping API Comparison 2026: EasyPost, Shippo, ShipEngine, RevAddress

Four services carry most USPS integration traffic in 2026: EasyPost, Shippo, ShipEngine, and RevAddress. This page prices them against each other using each vendor’s own published rates, checked August 23, 2026, and says which one wins at which volume.

The largest change since the March 2026 version of this comparison is not any of the four. It is that USPS itself began charging for address validation on August 1.

Three units, one bill

Every comparison of these services goes wrong in the same place: the four headline prices are denominated in different things.

• EasyPost, Shippo, and ShipEngine price labels. Address validation is bundled into label pricing or metered separately per call.
• RevAddress prices API requests. One pooled monthly budget covers validations, rates, batch jobs, and labels alike, with no per-call fee. The plan buys the infrastructure, not the postal data: DPV, rates, tracking, and labels all run on your own USPS license, so the USPS fee below is yours to pay directly.
• USPS prices address events, and as of August 1, 2026 it bills that directly to any account running on its own license. That fee sits underneath BYOK and inside a reseller’s markup.

A number that ignores the unit is not a comparison. So the tables below are split: one for labels, one for address lookups, with postage excluded from both and treated separately, because postage is usually the biggest line and it moves in the opposite direction from the fees.

What each charges now

EasyPost. Free Access with EasyPost’s wallet carriers is free for up to 3,000 labels a month, with a per-label fee above that; the fee amount is not published on the pricing page as of August 2026, and it was $0.08 when this comparison was first written in March. Bring Your Own Carrier Accounts is $20 a month plus a per-label fee. Enterprise is custom. Tracking runs $0.01 to $0.03 per shipment, advanced tracking $0.03. Insurance is 1% of declared value with a $1.00 minimum.

Shippo. API Starter is free with 30 labels a month included, then $0.07 per label with no ceiling. Services bought on their own bill at API Starter rates: $0.02 per US address validation, $0.08 per non-US validation, $0.02 per tracking request, $0.01 per rate generation. API Premier is custom.

ShipEngine. Free is $0 a month but restricted to ShipStation’s own carrier accounts, and address validation on Free runs only inside a Get Rates or Create Label action, never standalone. Advanced starts at $75 a month for 1,000 labels, with overage at $0.075 per label at the 1,000 tier, $0.065 at 5,000, and $0.060 at 10,000; the monthly prices for the 5,000 and 10,000 tiers are not published. The allowance is per endpoint rather than pooled. Enterprise is custom above 25,000 shipments a month.

RevAddress. Free is $0 for 1,000 requests a month, Starter $29 for 5,000, Growth $79 for 25,000, Pro $199 for 100,000, Enterprise $499. No per-call or per-label fee at any tier. USPS features run on your own USPS license at every plan, including Free.

USPS. $10 flat for the first 2,000 address events a month, then $4.50 per thousand to 10,000, $4.25 per thousand to 50,000, and $4.00 per thousand above that. Single tier for the whole month, partial thousands round up, signed license required.

Labels, fees only

Shippo’s column is 30 free labels subtracted, then $0.07 each. EasyPost’s is the free allowance subtracted, with the remainder left unpriced because the fee is not published; at the March 2026 rate of $0.08, ten thousand labels was $560 and fifty thousand was $3,760. The RevAddress column is the Pro plan price and nothing else, and every row of it runs on your own USPS license and your own Enterprise Payment Account, never on RevAddress credentials.

None of this includes postage, and postage is where the comparison usually turns. EasyPost, Shippo, and ShipEngine buy postage on carrier accounts they negotiated across their whole customer base and pass the discount to you. A RevAddress label buys postage on your own USPS account at whatever commercial rates that account has earned. For a small shipper, a platform’s discount on a Ground Advantage label can be worth more than its per-label fee costs. Compare your own invoices before you move labels anywhere.

Address lookups, fees only

The RevAddress column is the plan price plus the USPS fee for that volume, billed to your own Enterprise Payment Account. The plan limits are pooled, so those validation counts consume the whole budget and a workload that also rates or tracks needs the next tier or a tighter cache.

This is the asymmetry worth reading twice. If you buy a label for every address you validate, validation is effectively free everywhere and the label table decides it. If you validate far more addresses than you ship, per-call metering compounds and a flat plan wins by a large multiple. Checkout validation, CRM hygiene, and list cleaning all sit on that side of the line.

Architecture

The first row is the structural difference. Three of the four sit between you and USPS. That absorbs real work, and it absorbs the USPS rate limit, which is a genuine benefit and not a small one. It also means your postal access lives inside somebody else’s account.

What actually changed in 2026

USPS address validation stopped being free on August 1. Consumption-tier pricing, a signed license agreement, and a funded Enterprise Payment Account before your first call. The full curve and the license sequence are in what the USPS API actually costs. If you budgeted an integration on the free-API assumption, that is the number to redo first.

Web Tools is gone. The old XML API retired in January 2026 and returns errors rather than deprecation warnings. Every platform above migrated its backend to USPS v3 REST. If you still run a Web Tools adapter, the shutdown guide covers the move.

ShipEngine is becoming ShipStation API. Their pricing page says so directly and the docs have moved to a ShipStation domain. A rename and a consolidation, not a shutdown.

EasyPost’s plan enforcement landed in March. Accounts without a chosen plan moved into BYOCA or lost label generation. What changed after auto-enrollment has the detail.

Shippo restructured. The March 2026 version of this page quoted $0.05 a label and a Pro ladder running to $199. The published rate is now $0.07 a label with a 30-label free allowance, and the app Pro tier starts at $17.

USPS tightened access. CRID and MID enrollment, app-level approval, and license countersignature are now gates rather than formalities. The enrollment guide documents each step and the errors it produces.

Address validation, side by side

import easypost

client = easypost.EasyPostClient("EASYPOST_API_KEY")

address = client.address.create(
  street1="1600 Pennsylvania Ave NW",
  city="Washington",
  state="DC",
  zip="20500",
  country="US",
  verify=["delivery"],
)

if address.verifications.delivery.success:
  print(f"Valid: {address.street1}")
else:
  print(f"Invalid: {address.verifications.delivery.errors}")

from usps_v3 import USPSClient

client = USPSClient(api_key="rv_live_your_key_here")

result = client.addresses.validate(
  street_address="1600 Pennsylvania Ave NW",
  city="Washington",
  state="DC",
  zip_code="20500",
)

if result.dpv_confirmation == "Y":
  print(f"Valid: {result.address.street_address}")
else:
  print(f"Not confirmed: DPV={result.dpv_confirmation}")

EasyPost returns a success flag and an error list. RevAddress returns the DPV confirmation code USPS issued, plus the DPV footnotes: Y confirmed, D confirmed to the building with a missing secondary, S confirmed with an extra secondary USPS ignored, N not confirmed. Three of the four fail a boolean and each is a different repair, which is the whole argument for the raw code.

The honest routes

There is no single right answer, and the differences are worth understanding before you pick.

Free Census-based validation, no USPS license. Standardization, geocoding, and address extract against the US Census Bureau’s public address inventory. No credentials, no license, no per-lookup fee. It gets an address into correct postal form and returns street-level coordinates. It does not return DPV, ZIP+4, or any USPS deliverability flag, because those are USPS data and USPS data now requires a license. For list hygiene and geocoding it is the whole job. For “does mail arrive here,” it is not.

A reseller’s credentials. EasyPost, Shippo, or ShipEngine. You never sign a USPS agreement, never fund an Enterprise Payment Account, and never think about the 60-requests-per-hour limit. You pay a per-unit fee, your postal access lives in their account, and USPS-specific fields arrive normalized.

BYOK on your own license. You sign the USPS agreement, pay the USPS fee curve directly, and point RevAddress at your credentials. The full USPS suite then runs on your license: DPV with ZIP+4, CMRA, vacancy and business flags, rates, service standards, and tracking. We manage the OAuth lifecycle, encrypted credential storage, rate-limit budgeting, caching, and retries; the CRID, the MID, the EPA, and the USPS relationship stay yours. Every plan supports it, including Free.

RevAddress does not create labels on its own credentials for anyone. Label creation runs on your own USPS license and your own EPA, on the Pro plan, because postage has to be paid by the entity that owes it.

The decision framework

• Under 3,000 labels a month, multi-carrier: EasyPost Free Access. The allowance is genuinely generous and nothing here beats free.
• Under 30 labels a month: Shippo API Starter, also free, and simpler to stand up.
• Three or more carriers at any real volume: ShipEngine or EasyPost. Carrier abstraction is the product and paying for it is correct.
• On Shopify, BigCommerce, or WooCommerce with nobody writing code: Shippo. The plugins do work no API replaces.
• USPS-primary, more address lookups than labels: RevAddress. Validation is not metered per call, and at 25,000 lookups the published rates put $500 against $185.25 including the USPS fee.
• Standardizing and geocoding a list, no deliverability check needed: free Census-based validation. No license, no fee, no card.
• You need the postal relationship in your own name: BYOK, which among these four means RevAddress at every plan or EasyPost’s BYOCA at $20 a month.
• Over 50,000 labels a month: talk to sales at EasyPost or ShipEngine, and price your postage delta before you price anything else.

If you are not building an integration

Most people comparing shipping APIs have a spreadsheet, not a codebase. A donor list, a member roster, a customer export, and one mailing to get out the door. An API key is the wrong tool for that.

• List Clean — upload a CSV, get it back standardized, deduplicated, geocoded, and enriched. From $19. Free diagnosis of your file before you pay.
• Address File Audit — the $497 version for lists up to 25,000 rows, with duplicate clusters, county concentration, and what your bad rows cost per year.
• Batch validation — 50 addresses per call on your own USPS license, if you do want the API route.

Sources

• EasyPost, Pricing, checked August 23, 2026. Free Access allowance, BYOCA monthly price, tracking and insurance rates are published there; the per-label fee is not.
• Shippo, API pricing and app pricing, checked August 23, 2026.
• ShipEngine, Pricing, checked August 23, 2026. Plan prices, overage ladder, per-endpoint allowance and the ShipStation API rename banner are published there; the 5,000 and 10,000 tier monthly prices are not.
• USPS, Addresses API Tech Sheet, fee schedule effective August 1, 2026, published August 13, 2026.
• RevAddress plan prices and limits come from the pricing page, which renders from the same catalog the API meters against.

All four vendors restructure pricing on their own schedule; three of them did so between March and August 2026. Read their pages before you budget against these figures.

Start today

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