Bitrix24 integration with Trello

Bitrix24 and Trello Integration

Marketing department manages the content plan in Trello, while client tasks come through CRM in Bitrix24. Manager copies cards from Trello to B24 tasks manually, forgets half of them, mixes up deadlines. Designer moves a card to Done, but the B24 task stays "In Progress" for three more days — until someone notices. Two tools without connection multiply manual work and create blind spots.

How Synchronization Works

Trello provides REST API and webhooks mechanism. Bitrix24 has REST API with outbound webhooks on events. Middleware between them performs three functions: receives events, transforms data, sends updates to the paired system.

Trello (webhook) → Middleware → B24 REST API → task/CRM
B24 (event) → Outbound Webhook → Middleware → Trello REST API → card

Each "Trello board — B24 project" link is configured separately. One board can sync with one project, several boards — with several projects.

Structure Mapping

Trello and B24 organize work differently. Correspondence:

Description conversion: Trello stores text in Markdown, B24 in HTML. Middleware uses a parser (markdown-it or similar) to convert both ways. Images in description are downloaded and re-uploaded.

Status Synchronization via Lists

Moving a card between lists in Trello is a status change. The updateCard webhook with listAfter field tells middleware which list the card moved to. Middleware finds the correspondence in mapping table and updates the task stage in B24.

Reverse direction: when task stage changes in B24 (event ONTASKUPDATE), middleware moves the card to the corresponding list in Trello via PUT /1/cards/{id} with idList parameter.

The list mapping table is configured per board:

Automation via Power-Ups and REST API

Trello Power-Ups allow adding buttons and actions to cards. Middleware provides an endpoint for Power-Up that adds a "Create in B24" button to cards. On click — the card is created as a task in the selected project.

From B24 side — a robot in task business process. When a task is created with a specific tag (e.g., "trello"), the robot calls middleware webhook, which creates a card on the right board.

Additional automations:

• Card moved to "Done" → task in B24 closes + comment with timestamp
• New comment in card → comment to B24 task (and vice versa)
• Member added to card → observer added to B24 task
• Due date changed in B24 → updated on card

Migration from Trello to B24

Common scenario: team moves from Trello to Bitrix24 completely. Middleware supports full migration:

1. Export boards. Via Trello API (GET /1/boards/{id}/cards), export all cards with checklists, comments, attachments, and labels.
2. Create structure. In B24, create projects (groups) corresponding to boards. Kanban stages configured per Trello lists.
3. Transfer cards. Each card is created as a task via tasks.task.add. Checklists via task.checklistitem.add. Comments via task.commentitem.add with author and date.
4. Files. Attachments are downloaded from Trello, uploaded to B24 disk, linked to tasks.
5. Archived cards. Migrated as completed tasks with history preserved.

Migration volume: a board with 500 cards is transferred in 15–30 minutes (depends on attachment count and API limits).

API Rate Limiting

Trello API limits requests: 100 per 10 seconds per token, 300 per 10 seconds per key. B24 — 2 requests per second. Middleware manages rate limiting:

• Request queue with throttling
• Batch requests to B24 via batch method (up to 50 commands per call)
• For Trello — fields and card_fields parameters to reduce request count (fetch only needed fields)

What We Deploy

• Middleware for bidirectional sync between Trello boards and B24 projects
• Mapping of cards, lists, checklists, and participants
• Automatic status updates when cards move
• Power-Up for creating B24 tasks from Trello cards
• Full data migration from Trello to Bitrix24
• Comment and attachment synchronization
• Rate limiting and queue for working within API limits