Allegro API Guide
for Sellers 2026

Everything you need to integrate with Allegro's REST API. Authentication, key endpoints, rate limits, and webhooks — explained for e-commerce sellers and developers.

What Is the Allegro REST API?

The Allegro REST API is the primary programmatic interface for integrating with Poland's largest e-commerce marketplace. With over 20 million active buyers and 135,000 merchants, Allegro processes billions of zloty in gross merchandise value annually. The REST API replaced the legacy WebAPI (SOAP) in 2020 and is now the only supported integration method for new applications.

The API follows RESTful conventions with JSON payloads, uses OAuth 2.0 for authentication, and provides comprehensive coverage of the seller workflow: listing products, managing orders, handling returns, uploading images, and monitoring account health. All endpoints are documented at developer.allegro.pl, Allegro's official developer portal.

For sellers expanding to European marketplaces, Allegro's API is critical infrastructure. Unlike platforms such as Amazon (which uses SP-API) or eBay (which uses a combination of REST and legacy APIs), Allegro's modern REST API is relatively straightforward to integrate with — but it has unique conventions around product-based offers, category-specific parameters, and the Polish-language category tree that require careful handling.

This guide covers the essential concepts you need to build a working Allegro integration: obtaining API credentials, authenticating requests, creating and managing offers, processing orders, and subscribing to real-time events. Whether you are building a custom integration or evaluating tools like Marqetir that handle the API complexity for you, understanding these fundamentals will help you make informed decisions.

Last updated: March 2026

Authentication (OAuth 2.0)

Allegro uses OAuth 2.0 exclusively. There are no API keys or basic auth options. To get started, register your application in the Allegro Developer Portal (apps.developer.allegro.pl). You will receive a client_id and client_secret.

Two OAuth 2.0 Flows

Authorization Code Flow

For applications acting on behalf of a user. The seller authorizes your app through a browser redirect, and you exchange the authorization code for access + refresh tokens. Access tokens expire after 12 hours; refresh tokens after 3 months.

Client Credentials Flow

For server-to-server calls that don't require user context (e.g., browsing categories, searching public offers). The token is obtained by posting your client_id and client_secret to the token endpoint.

Token endpoint:

POST https://allegro.pl/auth/oauth/token

Include Authorization: Basic {base64(client_id:client_secret)} in the header.

Key API Endpoints

The Allegro REST API base URL is https://api.allegro.pl. The sandbox environment uses https://api.allegro.pl.allegrosandbox.pl. Below are the endpoints most critical for seller integrations.

MethodEndpointDescription
POST/sale/product-offersCreate or update a product-based offer
GET/sale/offersList your active offers with filters
GET/sale/categoriesBrowse the full category tree
GET/sale/matching-categoriesFind matching categories by keyword
GET/order/checkout-formsRetrieve orders and checkout data
PUT/order/checkout-forms/{id}/fulfillmentUpdate shipment and tracking info
GET/sale/offer-eventsPoll for offer change events
POST/sale/imagesUpload product images
GET/pricing/offer-fee-previewPreview fees for an offer before listing
GET/meGet current user account details

Getting Started: Step by Step

1

Register as an Allegro seller

Create a business seller account at allegro.pl. You need a valid Polish or EU business registration (NIP/VAT ID). Verify your identity and complete the onboarding process, which typically takes 1-3 business days.

2

Create an application in the Developer Portal

Go to apps.developer.allegro.pl and register a new application. Choose "Web application" for server-side integrations. Set your redirect URI (used during OAuth authorization). You will receive your client_id and client_secret.

3

Implement OAuth 2.0 authentication

Use the Authorization Code flow to obtain access and refresh tokens. Store the refresh token securely — you will need it to obtain new access tokens when they expire (every 12 hours). Implement automatic token refresh in your integration.

4

Test in the Sandbox environment

Allegro provides a full sandbox at allegro.pl.allegrosandbox.pl. Register a separate sandbox application, create test offers, and simulate the complete order flow before going live. The sandbox mirrors production behavior but uses test data.

5

Map your products to Allegro categories

Use the /sale/matching-categories endpoint to find the right category for each product. Allegro requires category-specific parameters (attributes) for each offer — retrieve these with /sale/categories/{id}/parameters. This mapping is the most time-consuming part of the integration.

6

Create your first offer via the API

Use POST /sale/product-offers to create a product-based offer. Include the required category parameters, at least one image, a title (up to 75 characters), description (HTML allowed), price, stock quantity, and shipping rates. The API returns the offer ID and its activation status.

Rate Limits

  • General limit: 9,000 requests/minute per application
  • Search endpoints: ~60 requests/minute
  • Image upload: 600 requests/minute
  • Offer creation: 9,000 requests/minute (batched)
  • Rate exceeded: HTTP 429 with Retry-After header
  • Headers returned: X-RateLimit-Limit, X-RateLimit-Remaining

Webhooks & Events

  • Offer events: GET /sale/offer-events (polling)
  • Order events: GET /order/event-stats
  • Event types: OFFER_ACTIVATED, OFFER_ENDED, OFFER_STOCK_CHANGED
  • Order types: BOUGHT, FILLED_IN, READY_FOR_PROCESSING
  • Polling interval: Recommended every 30-60 seconds
  • Event retention: Events available for 24 hours

Related Allegro Resources

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Allegro API — Frequently Asked Questions

Common questions about integrating with the Allegro REST API.