Stannp
Stannp is a direct mail platform that enables businesses to send physical postcards and letters programmatically via a REST API. The platform lets developers create campaigns, upload recipient lists, trigger individual mail pieces in real time, and track print and delivery status through webhooks and event endpoints. Authentication uses API key-based HTTP Basic Auth over HTTPS, and the API follows a simple JSON response envelope with success/data or success/error fields. Stannp serves businesses across the UK, US, and Canada with per-item pricing for letters and postcards at scale, and supports no-code integrations through Zapier and Make as well as official SDKs for PHP, Go, and C#.
Stannp publishes 7 API contracts indexed on the APIs.io network, including Account API, Campaigns API, Events API, and 4 more. Tagged areas include Direct Mail, Postcards, Letters, Print, and Physical Mail.
The Stannp catalog on APIs.io includes 1 event-driven AsyncAPI specification, 1 JSON-LD context, and 1 Spectral governance ruleset.
Stannp’s developer surface includes authentication, sandbox, documentation, API reference, getting-started guide, support, engineering blog, and 39 more developer resources.
What this lets a business do 1
Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →
What people ask Stannp 7
The questions people put to an LLM, and the jobs they hand an agent, that Stannp's APIs answer — each one linked to the operation that does it. Generated by API Evangelist
Kin Score
Markets this provider is in provisional
The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.
| Market | Position | Depth | Registered MCP server | Declares compatibility |
|---|---|---|---|---|
| HubSpot App Marketplace (CRM add-ons, outbound, performance marketing, chat) | long-tail | 18.1 | - | - |
Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.
Listed on Hagglebee
Classified listings for Stannp's APIs on Hagglebee, an agent-first classifieds site: stannp campaigns api
Standards implemented 1
Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.
APIs 7
Individual APIs this provider publishes, each with its own machine-readable definition.
Stannp Account API
Account balance and user information
Stannp Campaigns API
Manage batch direct mail campaigns
Stannp Events API
Record recipient engagement and conversion events
Stannp Groups API
Manage recipient groups
Stannp Letters API
Create, post, retrieve, and cancel letter mailpieces
Stannp Postcards API
Create, retrieve, and cancel postcard mailpieces
Stannp Recipients API
Manage individual recipients and bulk imports
Scroll for all 7
Open Collections 7
Open, tool-agnostic API collections (OpenAPI-derived and Bruno).
Stannp Direct Mail Account API
OPEN COLLECTIONStannp Direct Mail Account Campaigns API
OPEN COLLECTIONStannp Direct Mail Account Events API
OPEN COLLECTIONStannp Direct Mail Account Groups API
OPEN COLLECTIONStannp Direct Mail Account Letters API
OPEN COLLECTIONStannp Direct Mail Account Postcards API
OPEN COLLECTIONStannp Direct Mail Account Recipients API
OPEN COLLECTIONScroll for all 7
Agent Skills 4
Packaged agent skills for driving this provider's APIs from an AI assistant.
Build, price and book a Stannp campaign
AGENT SKILLSend a single Stannp postcard
AGENT SKILLSend a transactional Stannp letter
AGENT SKILLStannp API pricing
Prices published by Stannp, read 2026-10-28 from www.stannp.com/us/pricing.
| Plan | Price |
|---|---|
| Per mail piece (postcard, 1,500 volume, with starter plan) | $0.72 per mail piece | Includes print & postage Includes: Production, printing, postage, and mailing; color printing standard |
| Starter Plan | $12.00 per month Includes: Supported 24hr SLA, Live mail tracking, API access, Access templates; saving per mail item $0.14 |
Plan details, limits and sources →
Rate limits
- : 300 api requests
- : 600 api requests
- : 2000 api requests
Billed by: mail piece | includes print & postage · FinOps profile →
Pricing Plans 2
Published pricing tiers and plan structures.
Stannp Plans Pricing
PLANSRate Limits 1
Documented rate limits and quota policies.
Stannp Rate Limits
RATE LIMITSTerms of Service 1
What its API terms permit and prohibit, quoted from its own page.
Compliance 1
Attestations the provider states (SOC 2, ISO 27001 and others), quoted from its own trust page. APIs.io verifies none of them.
Eligibility 1
Who may sign up and where, quoted from its own terms.
AI Preferences 1
Its stance on AI training, inference and agents, quoted from its own pages.
FinOps 1
Cost, billing, and metering signals for API financial operations.
Stannp Finops
FINOPSEvent Specifications 1
AsyncAPI definitions for this provider's event-driven and streaming APIs.
Stannp Webhooks
ASYNCAPISemantic Vocabularies 1
JSON-LD contexts and semantic vocabularies used across these APIs.
Stannp Context
JSON-LDSpectral Rules 1
Spectral governance rulesets for linting and validating these APIs. Counts are the severity each rule declares, not results of running them.
Stannp — jsonschema rules
SPECTRALOpenAPI Overlays 14
Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.
Stannp Account Api Overlay
DERIVEDStannp Account Api Phrasing Overlay
GENERATEDStannp Campaigns Api Overlay
DERIVEDStannp Campaigns Api Phrasing Overlay
GENERATEDStannp Events Api Overlay
DERIVEDStannp Events Api Phrasing Overlay
GENERATEDStannp Groups Api Overlay
DERIVEDStannp Groups Api Phrasing Overlay
GENERATEDStannp Letters Api Overlay
DERIVEDStannp Letters Api Phrasing Overlay
GENERATEDStannp Postcards Api Overlay
DERIVEDStannp Postcards Api Phrasing Overlay
GENERATEDStannp Recipients Api Overlay
DERIVEDStannp Recipients Api Phrasing Overlay
GENERATEDScroll for all 14
JSON Schema 3
Standalone JSON Schema definitions for this provider's data models.
Examples 3
Example request and response payloads for these APIs.
Security Posture 4
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Stannp Trust Center
HIPAA, ISO 27001, ISO 9001, GDPR, ICO registration ZA134992 (UK Data Processor), USPS CASS certification, Royal Mail PAF accreditation, Royal Mail Mail Made Easy partner, Securi...
SECURITYAgentic Access (API Evangelist recommendations) 1
Recommended x-agentic-access execution contracts for AI agents.
Resources
Get Started 5
Portal, sign-up, and the first successful call
Documentation 3
Reference material describing how the API behaves
Agent Surfaces 4
MCP servers, agent skills, and machine-readable catalogs
Design & Contract 7
Pagination, idempotency, versioning, errors, and events
Scroll for all 7
Build 4
SDKs, sample code, and the tooling you integrate with
Access & Security 6
Authentication, authorization, and security posture
Operate 4
Status, limits, changes, and where to get help
Commercial 6
Pricing, plans, and the legal terms of use
Company 3
The organization behind the API
Other 4
Properties that don't map to a standard resource type
Source (apis.yml)
Stannp API — frequently asked questions
Does Stannp have an API?
Yes. APIs.io lists 7 APIs from Stannp, including Stannp Account API, Stannp Campaigns API and Stannp Events API, and 4 more.
Is there an OpenAPI specification for the Stannp API?
Yes. APIs.io indexes 7 OpenAPI specifications for Stannp, each linked for download from this page.
How do I authenticate with the Stannp API?
Stannp uses bearer-token authentication (http/apiKey · 3 schemes). The details are profiled on APIs.io as Stannp Authentication.
How much does the Stannp API cost?
Stannp publishes its prices; its Per mail piece (postcard, 1,500 volume, with starter plan) plan is $0.72 per mail piece | Includes print & postage as of 2026-10-28. APIs.io lists 2 pricing plans for Stannp, with each plan's price, limits and inclusions under Pricing on this page.
Is the Stannp API ready for AI agents?
Stannp has a Kin Score of 72.0 out of 100 (exemplar) and an Agent Readiness score of 43.0 (agent-native), scored by API Evangelist on 2026-11-13.
Work with this as data
Every provider here is available over the APIs.io API and to AI agents over MCP.