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FeaturesagentOS Direct DebitUpdated March 13, 2026

Mandate Registration with Modulr (AUDDIS Submission)

Mandate Registration with Modulr (AUDDIS Submission)

Introduced in v1.0.25

When a tenant completes the mandate form, the service automatically submits their bank details to Modulr via the AUDDIS API to register the Direct Debit mandate on the BACS network. This is the final step in activating a mandate and enabling future rent collections.

How It Works

1. Form Submission Triggers AUDDIS Registration

On successful completion of the mandate form, the service sends an AUDDIS registration request to Modulr containing:

  • Tenant bank details — account number, sort code, and account holder name as entered on the form
  • Service User Number (SUN) — the letting agent's BACS SUN, scoped per customer (multi-tenant)

This request is sent synchronously at submission time. If the Modulr API request fails, the mandate is not marked as submitted and the error is surfaced for retry.

2. Mandate Reference & Submission Date Stored

On a successful AUDDIS submission, the following are recorded against the mandate record:

FieldDescription
modulr_mandate_referenceModulr's unique identifier for this mandate — used for all future collection requests
auddis_submission_dateThe date the AUDDIS request was submitted — used for BACS cycle and working day calculations
statusSet to pending_submission immediately after a successful submission

3. Async Activation Confirmation

Because AUDDIS operates within the BACS clearing cycle, mandate acceptance by the banking network is not instantaneous. Modulr confirms activation asynchronously via one of two mechanisms:

  • Webhook — Modulr posts an event to the service when the mandate is accepted. This is the preferred path and results in the fastest status update.
  • Polling — If a webhook is not received within the expected window, the service polls Modulr for the mandate status until confirmation is received.

Once activation is confirmed:

  1. The mandate status is updated from pending_submission → active.
  2. The letting agent receives an automated notification that the tenant's mandate is live and ready for collection scheduling.

Mandate Status Lifecycle

Form Submitted
      │
      ▼
[AUDDIS request sent to Modulr]
      │
      ▼
 pending_submission  ──── webhook / poll ────▶  active
StatusMeaning
pending_submissionAUDDIS request accepted by Modulr; awaiting BACS network confirmation
activeMandate confirmed on the BACS network; ready for collection

Agent Notification

When a mandate transitions to active, the letting agent is notified automatically. This notification signals that:

  • The Direct Debit mandate is registered and live.
  • Collections can now be scheduled against this mandate.
  • The tenant's mandate is visible and manageable via the API.

Error Handling

  • If the Modulr AUDDIS API returns an error at submission time, the mandate status remains unchanged and the failure is logged.
  • The mandate can be resubmitted once the underlying issue (e.g. invalid bank details, SUN configuration) is resolved.
  • Mandates stuck in pending_submission beyond the expected BACS processing window will be flagged for review.

Related

  • Mandate Form — The multi-step tenant-facing form that precedes AUDDIS submission
  • BACS & Working Day Logic — How collection dates are calculated on the BACS network
  • Collections — Scheduling and submitting collections against active mandates