PostGrid

PostGrid is a physical mail automation platform that provides REST APIs for sending printed letters, postcards, checks, and self-mailers at scale. It offers a Print & Mail API that enables developers to programmatically trigger and manage direct mail campaigns with full personalization and tracking support. PostGrid also provides US & Canada Address Verification and International Address Verification APIs covering 245+ countries for real-time autocomplete, standardization, geocoding, and bulk batch verification. The platform supports both test and live API environments, integrates natively with Salesforce, HubSpot, Zapier, and Marketo, and handles postage, printing, and delivery end-to-end.

PostGrid publishes 1 API on the APIs.io network: Print & Mail API. Tagged areas include Direct Mail, Print & Mail, Address Verification, Address Validation, and Postcards.

The PostGrid catalog on APIs.io includes 1 JSON-LD context.

PostGrid’s developer surface includes documentation, engineering blog, changelog, pricing, support, and 10 more developer resources.

🌐 Visit website 📡 Source on GitHub

31.0/100 thin ▬ flat Agent 16/100 agent aware Full breakdown ↓
scored 2026-08-25 · rubric v0.14.0

AccessPaidFree trial

3 APIs

Direct MailPrint & MailAddress Verification Address Validation Postcards Letters ChecksPhysical MailMail AutomationAddress Autocomplete Geocoding

Kin Score

Kin Score How this is scored →
scored 2026-08-25 · rubric v0.14.0

Composite quality — 31.0/100 · thin

Contract Quality 9.3 / 25

Developer Ergonomics 1.9 / 20

Access Clarity 7.9 / 20

Operational Transparency 4.4 / 13

Contract Governance 0.0 / 12

Discoverability 7.4 / 10

Agent readiness — 16/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Surface 0 / 5

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/postgrid: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 3

Individual APIs this provider publishes, each with its own machine-readable definition.

Rate Limits 1

Documented rate limits and quota policies.

Postgrid Rate Limits

3 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Operate 4

Status, limits, changes, and where to get help

ChangeLog

StatusPage

Support

RateLimits

Commercial 3

Pricing, plans, and the legal terms of use

Pricing

Pricing

Plans

Plans

FinOps

FinOps

Company 3

The organization behind the API

Website

Website

LinkedIn

Blog

Blog

Other 2

Properties that don't map to a standard resource type

Developers

Developers

Source (apis.yml)

aid: postgrid
name: PostGrid
description: PostGrid is a physical mail automation platform that provides REST APIs for sending printed letters, postcards,
  checks, and self-mailers at scale. It offers a Print & Mail API that enables developers to programmatically trigger and
  manage direct mail campaigns with full personalization and tracking support. PostGrid also provides US & Canada Address
  Verification and International Address Verification APIs covering 245+ countries for real-time autocomplete, standardization,
  geocoding, and bulk batch verification. The platform supports both test and live API environments, integrates natively with
  Salesforce, HubSpot, Zapier, and Marketo, and handles postage, printing, and delivery end-to-end.
type: Index
accessModel:
  pricing: paid
  onboarding: unknown
  trial: true
  try_now: false
  public: false
  label: Paid (free trial)
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/postgrid.png
tags:
- Direct Mail
- Print & Mail
- Address Verification
- Address Validation
- Postcards
- Letters
- Checks
- Physical Mail
- Mail Automation
- Address Autocomplete
- Geocoding
url: https://raw.githubusercontent.com/api-evangelist/postgrid/refs/heads/main/apis.yml
created: '2026-06-12'
modified: '2026-06-12'
specificationVersion: '0.23'
apis:
- aid: postgrid:print-mail-api
  name: PostGrid Print & Mail API
  description: A REST API for programmatically sending letters, postcards, checks, and self-mailers. Handles printing, postage,
    and delivery with support for templates, contacts, tracking, webhooks, and both test and live modes. Authenticated via
    x-api-key header.
  humanURL: https://docs.postgrid.com/
  baseURL: https://api.postgrid.com
  tags:
  - Direct Mail
  - Letters
  - Postcards
  - Checks
  - Self-Mailers
  - Print
  - Mail Automation
  properties:
  - type: Documentation
    url: https://docs.postgrid.com/
  - type: OpenAPI
    url: https://postgrid.readme.io/llms.txt
  - type: PythonSDK
    url: https://github.com/postgrid/postgrid-python
  - type: NodeSDK
    url: https://github.com/postgrid/postgrid-node
  - type: Examples
    url: https://github.com/postgrid/postgrid-examples
- aid: postgrid:address-verification-api
  name: PostGrid US & Canada Address Verification API
  description: A REST API for real-time address autocomplete, verification, and standardization for US and Canadian addresses.
    Supports CASS-certified validation, geocoding (latitude/longitude), freeform address parsing, and batch verification for
    large-scale processing. Authenticated via x-api-key header with a default rate limit of 5 requests per second.
  humanURL: https://avdocs.postgrid.com/
  baseURL: https://api.postgrid.com/addver
  tags:
  - Address Verification
  - Address Validation
  - Address Autocomplete
  - CASS
  - Geocoding
  - US
  - Canada
  properties:
  - type: Documentation
    url: https://avdocs.postgrid.com/
- aid: postgrid:international-address-verification-api
  name: PostGrid International Address Verification API
  description: A REST API for verifying, standardizing, and autocompleting addresses across 245+ countries worldwide. Supports
    real-time lookups and bulk verification workflows. Authenticated via x-api-key header.
  humanURL: https://intdocs.postgrid.com/
  baseURL: https://api.postgrid.com/addver
  tags:
  - Address Verification
  - Address Validation
  - International
  - Global
  - Address Autocomplete
  properties:
  - type: Documentation
    url: https://intdocs.postgrid.com/
common:
- type: DomainSecurity
  url: security/postgrid-domain-security.yml
- type: Website
  url: https://www.postgrid.com/
- type: Documentation
  url: https://docs.postgrid.com/
- type: Developers
  url: https://www.postgrid.com/developers/
- type: GitHubOrganization
  url: https://github.com/postgrid
- type: LinkedIn
  url: https://www.linkedin.com/company/postgrid
- type: X
  url: https://x.com/postgridinc
- type: Blog
  url: https://www.postgrid.com/blog/
- type: ChangeLog
  url: https://www.postgrid.com/updates-and-releases/
- type: Pricing
  url: https://www.postgrid.com/pricing/
- type: StatusPage
  url: https://status.postgrid.com/
- type: Support
  url: https://www.postgrid.com/help-support/
- type: Plans
  url: plans/postgrid-plans-pricing.yml
- type: RateLimits
  url: rate-limits/postgrid-rate-limits.yml
- type: FinOps
  url: finops/postgrid-finops.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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PostGrid

Kin Score

APIs 3

PostGrid Print & Mail API

PostGrid US & Canada Address Verification API

PostGrid International Address Verification API

Pricing Plans 1

Postgrid Plans Pricing