Best Address Validation APIs

Best overall: Lob Address Verification

███████▒░░ 74 / 100 data score

Lob Address Verification is a REST API for validating, standardizing, and autocompleting postal addresses, covering all US territories through USPS CASS Cycle O certification and 240+ international territories. It targets developers and businesses needing real-time checkout validation, bulk mailing list hygiene, or CRM data cleansing. Pricing starts at $0.025 per 1,000 lookups with a free tier of 300 live US verifications per month and unlimited sandbox requests, plus enterprise plans via sales. The API ships official SDKs for eight languages and holds SOC 2 Type II, HIPAA, GDPR, and ISO 27001 certifications.

From $0.03 1,000 lookups · free tier available.

How it stacks up

• ✓ Lob Address Verification offers a free tier while Loqate Address Verification does not, so Lob Address Verification is easier to trial before committing.
• ✓ Lob Address Verification offers a free tier while PostGrid Address Verification does not, so Lob Address Verification is easier to trial before committing.
• ✓ For coding-agent use, Lob Address Verification scores higher on agent-friendliness (40 vs 20).

Best for: Prototypes and side projects - free to start, no sales call; Regulated or enterprise workloads - compliance attestations and an enterprise plan; Teams needing broad API coverage out of the box.

The catch: The cheapest US verification ($0.025 per 1,000) and very developer-friendly, but autocomplete is US-only and international coverage is thinner than the global data vendors.

Lob Address Verification profile → · Lob Address Verification vs Loqate Address Verification →

At a glance

Quick pick by use case

If you only have thirty seconds, find your situation:

• If you want the strongest all-round pick, pick Lob Address Verification - our default pick: strongest across pricing, trust and breadth.
• If you want to start free, pick Lob Address Verification - free tier: Developer plan: 300 free live US address verification API requests per month at no cost;….
• If you're buying for a regulated or large team, pick Lob Address Verification - for regulated or large teams: SOC 2 Type II, HIPAA, published SLA.
• If you want the lowest published entry price, pick PostGrid Address Verification - from $18 month to start; compare on your real usage, not the entry price.
• If you're wiring this into coding agents or AI workflows, pick Loqate Address Verification - easiest to wire up programmatically: MCP server + llms.txt.
• If you want the broadest documented surface, pick Melissa - 26 documented actions; breadth isn't quality, but it's the most to build on.

The picks in depth

• #1 Lob Address Verification

  ███████▒░░ 74 / 100
  • Best overall
  • Best free pick
  • Best for enterprise

  Lob Address Verification is a REST API for validating, standardizing, and autocompleting postal addresses, covering all US territories through USPS CASS Cycle O certification and 240+ international territories. It targets developers and businesses needing real-time checkout validation, bulk mailing list hygiene, or CRM data cleansing. Pricing starts at $0.025 per 1,000 lookups with a free tier of 300 live US verifications per month and unlimited sandbox requests, plus enterprise plans via sales. The API ships official SDKs for eight languages and holds SOC 2 Type II, HIPAA, GDPR, and ISO 27001 certifications.

  PricingHybrid · from $0.03 1,000 lookups · free tier ✓

  TrustSOC 2 Type II · HIPAA · GDPR · ISO 27001

  Does

  • USPS CASS certified
  • International coverage
  • Address autocomplete
  • Bulk / batch

  Used byCurrent, CareWell, BlueChip Financial

  Strengthstransparent public pricing · a free tier · self-serve signup

  The catchThe cheapest US verification ($0.025 per 1,000) and very developer-friendly, but autocomplete is US-only and international coverage is thinner than the global data vendors.

  ScoresAgent 40 · Pricing 100 · Setup 100 · Docs 15 · Procurement 100 · Trust 90

  Lob Address Verification profile →

• #2 Loqate Address Verification

  ███████▒░░ 75 / 100
  • Best for agents

  Loqate Address Verification is a REST API for validating, capturing, cleansing, and geocoding postal addresses across 250 countries and territories, with postal certification for the US (USPS CASS), Australia (AMAS), Canada (SERP), and the UK (Royal Mail PAF). It suits e-commerce checkout, customer onboarding, KYC workflows, and mailing list hygiene. Pricing is credit-based with published rates (US address capture at 4.7 cents each, starting at $100), a 45-day free trial with no credit card required, and enterprise plans available. The platform holds SOC 2 Type 2, ISO 27001, PCI DSS, and GDPR certifications, and counts IBM, Oracle, Sephora, and JetBlue among its customers.

  PricingUsage · from $100 credit bundle (e.g. $100 buys credits; US address capture at 4.7¢ each) · free tier ✗

  TrustSOC 2 Type II · GDPR · ISO 27001 · PCI DSS

  Does

  • USPS CASS certified
  • International coverage
  • Address autocomplete
  • Geocode append
  • Bulk / batch
  • Rooftop precision

  Used byIBM, Oracle, Fanatics, Sephora

  Strengthstransparent public pricing · self-serve signup · SOC 2 Type II

  The catchThe broadest global coverage (250 countries, CASS/SERP/PAF/AMAS certified), but pricing is credit-bundle based and it carries more enterprise setup than the dev-first pure-plays.

  ScoresAgent 75 · Pricing 85 · Setup 75 · Docs 45 · Procurement 85 · Trust 85

  Loqate Address Verification profile →

• #3 PostGrid Address Verification

  ██████▓░░░ 68 / 100
  • Cheapest to start

  PostGrid Address Verification is a REST API that autocompletes, validates, standardizes, and geocodes addresses across 250+ countries, with postal authority certifications for the US (USPS CASS), Canada (Canada Post SERP), UK (Royal Mail PAF), and Australia (Australia Post AMAS). It suits checkout flows, CRM hygiene, mailing list cleansing, and bulk batch processing up to one million addresses per API call. Pricing starts at $18 per month with 500 free trial lookups and self-serve signup, though international coverage beyond the US and Canada requires a separate higher-tier product. The service holds SOC 2 Type II, HIPAA, GDPR, and PCI DSS compliance, and offers SDKs for Node.js/TypeScript and Python.

  PricingHybrid · from $18 month · free tier ✗

  TrustSOC 2 Type II · HIPAA · GDPR · PCI DSS

  Does

  • USPS CASS certified
  • International coverage
  • Address autocomplete
  • Geocode append
  • Bulk / batch

  Used byMutual of Omaha, Cognizant, Oura, Leon's

  Strengthstransparent public pricing · self-serve signup · SOC 2 Type II

  Avoid ifYou want to try it free before paying

  ScoresAgent 40 · Pricing 85 · Setup 70 · Docs 45 · Procurement 85 · Trust 85

  PostGrid Address Verification profile →

• #4 Melissa

  ██████░░░░ 63 / 100
  • Broadest surface

  Melissa provides global data quality APIs to verify, clean, match, and enrich people data, including address, email, phone, and identity verification across 240+ countries and territories. Pricing is published and self-serve, and three SDKs are available. The platform carries SOC 2 Type 2, HIPAA, and GDPR compliance with a published SLA.

  PricingHybrid · free tier ✓

  TrustSOC 2 Type II · HIPAA · GDPR

  Does

  • International coverage
  • Address autocomplete
  • Geocode append
  • Bulk / batch

  Strengthstransparent public pricing · a free tier · self-serve signup

  ScoresAgent 20 · Pricing 75 · Setup 75 · Docs 45 · Procurement 90 · Trust 75

  Melissa profile →

• #5 Smarty (US & International Address Verification)

  ██████▒░░░ 65 / 100

  Smarty is a REST API for US and international address verification, offering USPS CASS-certified validation with DPV, ZIP+4, and geocoding for US addresses, plus street-level verification across 249 countries. It suits ecommerce checkout, mailing list hygiene, logistics, KYC onboarding, and healthcare workflows. Plans start at $50/month with a 1,000-lookup trial, self-serve signup, and SDKs for nine languages. SOC 2 Type 2 certified and GDPR compliant; HIPAA compliance and BAAs require an Enterprise plan.

  PricingSubscription · from $50 month · free tier ✗

  TrustSOC 2 Type II · HIPAA · GDPR

  Does

  • USPS CASS certified
  • International coverage
  • Address autocomplete
  • Geocode append
  • Bulk / batch
  • Rooftop precision

  Used byNASA, Uber, Chase Bank, Cox Communications

  Strengthstransparent public pricing · self-serve signup · SOC 2 Type II

  The catchFast, accurate, and well-documented, but there is no recurring free tier (42-day trial only) and international verification is a separate, pricier product.

  ScoresAgent 50 · Pricing 85 · Setup 60 · Docs 35 · Procurement 85 · Trust 75

  Smarty (US & International Address Verification) profile →

• #6 Service Objects DOTS Address Validation

  ████▓░░░░░ 47 / 100

  Service Objects DOTS Address Validation is a USPS CASS-certified REST API for validating, correcting, and standardizing postal addresses across the US, Canada, and 250-plus countries, used for e-commerce checkout, CRM hygiene, and fraud detection. A one-time 500-transaction trial key is available without a sales call, but production pricing requires contacting sales. The service holds SOC 2 Type 1 and PCI DSS certifications, complies with GDPR, and publishes an SLA. SDKs are available for .NET, Python, and Node.js, and a multi-language MCP server is also offered.

  PricingSales-led · free tier ✗

  TrustSOC 2 Type I · GDPR · PCI DSS

  Does

  • USPS CASS certified
  • International coverage
  • Geocode append

  Used byAmazon, Microsoft, Mastercard, American Express

  Strengthsself-serve signup · SOC 2 Type I · GDPR

  Avoid ifYou need transparent pricing up front

  ScoresAgent 60 · Pricing 15 · Setup 75 · Docs 15 · Procurement 55 · Trust 63

  Service Objects DOTS Address Validation profile →

• #7 Precisely Verify (Address Verification)

  █████▒░░░░ 55 / 100

  Precisely Verify is an enterprise address validation API from Precisely that covers 250+ countries, with USPS CASS Cycle O, Canada Post SERP, and Royal Mail PAF certifications alongside FedRAMP authorization for government use. It handles address standardization, geocoding, autocomplete, and bulk geo-addressing via a REST API with OAuth2 auth and SDKs for Python, Java, Node.js, C#, Android, and iOS. Pricing is not published and requires a custom quote, though a one-time 30-day free trial with 2,500 credits is available without a credit card. The platform holds SOC 2 Type II, HIPAA, GDPR, and ISO 27001 compliance, making it suited to regulated industries and high-volume enterprise data pipelines.

  PricingSales-led · free tier ✗

  TrustSOC 2 Type II · HIPAA · GDPR · ISO 27001

  Does

  • USPS CASS certified
  • International coverage
  • Address autocomplete
  • Geocode append
  • Bulk / batch

  Used byWillis RE, Poste Maroc, New Zealand Superannuation Fund, Belfius

  Strengthsself-serve signup · SOC 2 Type II · HIPAA

  Avoid ifYou need transparent pricing up front

  ScoresAgent 65 · Pricing 15 · Setup 60 · Docs 45 · Procurement 55 · Trust 90

  Precisely Verify (Address Verification) profile →

• #8 Radar Geocoding API

  ███████░░░ 69 / 100

  Radar Geocoding API converts addresses to coordinates and coordinates to addresses via forward, reverse, and IP geocoding, covering 195+ countries with varying coverage tiers. It targets developers building store locators, delivery tracking, and content localization apps, with mobile SDKs for iOS, Android, React Native, and Flutter. Pricing starts at $0.50 per 1,000 requests with a 100,000 request per month free tier and self-serve signup. The service is SOC 2 Type 2 certified and GDPR compliant, with customers including Lululemon, Pizza Hut, and TaskRabbit.

  PricingHybrid · from $0.50 1,000 requests · free tier ✓

  TrustSOC 2 Type II · GDPR

  Used byDICK'S Sporting Goods, Inspire Brands, bet365, Pizza Hut

  Strengthstransparent public pricing · a free tier · self-serve signup

  ScoresAgent 45 · Pricing 100 · Setup 85 · Docs 45 · Procurement 100 · Trust 40

  Radar Geocoding API profile →

See all 15 Address Validation APIs compared →

How we rank

The headline score is the average of six 0-100 axes computed only from each API’s published, sourced fields: agent-friendliness, pricing transparency, setup speed, docs quality, procurement ease, and trust readiness. An unknown signal scores 0 for its axis - we credit what’s confirmed, never guess. The score is one input, not the verdict: we lead with each pick’s trade-off, and where a job has only one real option we say so rather than crown it. Full method on the methodology page.

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• ✓ Every field cited. Each profile links the source for every claim - check us.
• ✓ Public audit log. Every change to this data is recorded per field, with who changed it and why.
• ✓ Published, deterministic methodology. The score is a formula over the same fields you can see - recompute it yourself.
• ✓ Zero affiliate links, zero ads, zero paid placement. Money never moves rank.
• ✓ No reviews yet - and we say so rather than synthesizing them.

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