Shipping API Comparison 2026 — Pricing by Volume

If you’re building shipping into your app in 2026, you’ve got four real options for USPS integration: EasyPost, Shippo, ShipEngine, and RevAddress. Each makes different trade-offs on pricing, architecture, and developer experience.

This isn’t a marketing page — it’s the comparison I wish existed when I was evaluating these services. Real pricing, real code, real trade-offs.

The pricing math (verified March 2026)

Every shipping API charges differently. EasyPost charges $0.08/label (with 3,000 free/mo on their Free Access Wallet plan, or $20/mo + $0.08/label on the BYOCA plan). Shippo charges $0.05/label pay-as-you-go (or $19–$199/mo Pro plans). ShipEngine uses tiered plans ($75–$600/mo). RevAddress charges flat monthly with no per-label fees.

At low volume, EasyPost wins. Their 3,000 free labels/month is genuinely generous. If you ship under 3K/month, EasyPost’s Free Access is hard to beat on price alone.

The crossover point is ~4,000 labels/month. That’s where flat pricing starts saving real money. At 10,000 labels/month, EasyPost costs $560/mo vs RevAddress at $79/mo — that’s $5,772/year in savings. At 50,000/month, the gap is $42,732/year.

Architecture differences

This matters more than pricing for most developers:

Key differentiator: EasyPost, Shippo, and ShipEngine are all middlemen — they hold USPS credentials, negotiate rates, and add a markup. RevAddress gives you a managed USPS-focused layer over USPS v3 with flat pricing, a free proof wedge, and optional BYOK. If you only need USPS, you’re paying a multi-carrier tax with the others.

When to pick each one

Pick EasyPost if you need 100+ carriers and money isn’t a constraint. Their multi-carrier support is genuinely the most comprehensive. But you’ll pay $0.08/label for it.

Pick Shippo if you’re on Shopify or a platform that has a native Shippo integration. Their platform integrations are their real strength, not the raw API.

Pick ShipEngine if you need multi-carrier with more predictable pricing than EasyPost. Their flat tiers make budgeting easier.

Pick RevAddress if you primarily ship USPS and want:

• Managed USPS-focused workflow coverage (no middleman markup)
• Flat monthly pricing that doesn’t scale with volume
• BYOK — bring your own USPS credentials for full control
• Open-source SDKs you can audit and self-host

Code comparison

Here’s address validation across all four. This is the most common API call — validate before you ship.

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 deliverable: DPV={result.dpv_confirmation}")

Both work. The difference: EasyPost proxies your request through their infrastructure and charges $0.08 for it. RevAddress runs the call through a USPS-focused managed layer and includes address validation inside the monthly plan.

The March 2026 context

Three things in early 2026 changed the calculus:

1. USPS v3 REST API is the required migration target. The old Web Tools XML API was retired January 2026 — it doesn’t just return deprecation warnings, it returns errors. Every shipping platform had to migrate their backend.

2. EasyPost changed their pricing. The new per-label fee structure hit in January. March 17, 2026 is the auto-enrollment date for accounts that have not chosen a plan: they move into BYOCA ($20/mo + $0.08/label) if a payment method is on file, or lose label generation if they do not.

3. USPS Access Control changes (April 2026). USPS is tightening API access — CRID/MID enrollment, app-level approval, stricter rate limits. Services without proper enrollment will lose access.

RevAddress holds a USPS-approved application ID (REVASSEROSSHIP) with CRID and MID properly enrolled. This matters because if your shipping provider hasn’t completed USPS enrollment, your API access could break in April.

Migration from EasyPost

If you’re moving from EasyPost to RevAddress, here’s the step-by-step:

1. Get your API key at revaddress.com/signup — takes 30 seconds
2. Install the SDK:

pip install usps-v3

npm install usps-v3

3. Replace the address validation call (see code comparison above)
4. Replace label creation:

# EasyPost: create shipment, then buy
shipment = client.shipment.create(
  from_address=from_addr,
  to_address=to_addr,
  parcel=parcel,
)
bought = client.shipment.buy(
  shipment.id,
  rate=shipment.lowest_rate(),
)
label_url = bought.postage_label.label_url

# RevAddress: single call, USPS-focused layer
label = client.labels.create(
  from_address=from_addr,
  to_address=to_addr,
  weight=weight_oz,
  mail_class="USPS_GROUND_ADVANTAGE",
  processing_category="MACHINABLE",
)
label_url = label.label_url

5. Test with your real addresses — RevAddress validates against USPS DPV (Delivery Point Validation), so you get the same accuracy as going direct
6. Switch your environment variable — EASYPOST_API_KEY → REVADDRESS_API_KEY

The honest trade-offs

RevAddress is not the right choice if:

• You ship with FedEx, UPS, and DHL alongside USPS — you’d need a multi-carrier platform
• You need carrier-negotiated rates (we pass through USPS Commercial rates, not custom-negotiated)
• You need on-premise deployment — our API runs on Cloudflare’s edge network

RevAddress is the right choice if:

• USPS is your primary or only carrier
• Per-label fees are eating into your margins
• You want to bring your own USPS credentials (BYOK)
• You want open-source SDKs you can audit
• You want a USPS-focused layer instead of paying a per-label middleman

Bottom line

At 1,000+ labels/month, the per-label pricing model costs more than flat monthly. At 10,000/month, you’re leaving nearly $9,000/year on the table with EasyPost. That’s the math.

Check the full pricing breakdown or try the API — the free proof surface gets you live address and rate validation first, then protected workflows expand as you need them.

Related

• EasyPost March 17 Enforcement: Migration Options
• USPS Web Tools Shutdown: Complete Migration Guide
• USPS v3 Address Validation Quickstart
• Full API Reference
• Pricing