Connecting to FIRS MBS via Peppol: Step-by-Step Onboarding

Why a runbook matters

Nigerian onboarding to FIRS MBS is process-heavy. The Peppol parts are well-defined; the Nigerian parts — TIN registration, participant scheme alignment, sandbox cycles, and rollout sequencing across multiple subsidiaries — are where projects slip.

This guide is the runbook our Nigerian customers use. Adapt the timing to your scope, but follow the order.

Step 1 — Pick the Access Point provider

The right shortlist looks like the Slovakia AP buyer's guide and our generic how to choose a Peppol Access Point. Cross-check the provider against FIRS public statements and the OpenPeppol directory. Add three Nigeria-specific dimensions:

• Live FIRS MBS integration. Not "we are evaluating MBS"; live, in production, with reference customers.
• Naira / cross-border handling. Multi-currency invoices, withholding tax fields, FIRS-specific extensions all working today.
• Local availability commitments. A relevant SLA for the Nigerian business day.

Verify the provider's Peppol Service Provider identifier on the OpenPeppol public directory.

Step 2 — Register the Nigerian participant

Your provider does this for you, but you should know what is happening:

1. Decide the Peppol participant identifier scheme — typically tied to your FIRS TIN.
2. The provider's SMP publishes a service group entry containing the supported document profiles (Peppol BIS Billing 3.0, Self-Billing 3.0, Credit Note).
3. The OpenPeppol SML (DNS-based discovery) becomes resolvable for your participant within minutes.
4. Verify with dig +short against the SML — your provider's AP endpoint should appear at the expected hash.

Step 3 — Map your ERP fields to UBL

The mapping list is unglamorous but it is the work. Cover at minimum:

• Header — supplier, customer, currency, issue date, due date, document type code (380 invoice, 381 credit note).
• TIN and VAT — supplier and customer TINs in the right scheme; VAT identifier where applicable.
• Withholding tax — cac:WithholdingTaxTotal if your invoices carry WHT.
• Lines — quantity, unit code, unit price, line extension amount, tax category and rate.
• Allowances and charges — cac:AllowanceCharge at header and line level.
• Payment — payment means code, IBAN/account, payment terms.

A pure transform from your ERP export to UBL is the right architectural shape — make it deterministic, version-controlled, and unit-testable.

Step 4 — Validation pipeline

Before any document leaves your AP it must pass:

1. UBL 2.1 XSD — structural.
2. EN 16931 Schematron — CEN baseline.
3. Peppol BIS 3.0 Schematron — Peppol baseline.
4. Nigerian extensions — where FIRS publishes them.
5. Code-list checks — eDEC code lists for currencies, units, country codes.

A error blocks. A warning is logged. Read invoice validation errors you can prevent for the canonical list of recoverable errors.

Step 5 — Sandbox cycle

The FIRS sandbox / pilot environment should see at least:

• 50+ representative invoices across product types and tax cases.
• 10+ credit notes.
• 5+ self-billing scenarios if applicable.
• A failure scenario where AP delivery is intentionally interrupted to validate retry behaviour.
• A receipt (MLR) round-trip.

Document each test outcome with the Peppol message ID and the FIRS sandbox correlation ID.

Step 6 — Production cutover

The cutover sequence we use:

1. Freeze ERP-side master-data changes for 24 hours.
2. Switch the SMP entry from sandbox profile to production profile (your provider does this).
3. Issue the first 10 production invoices manually-validated post-send.
4. Watch the inbound channel for live receipts.
5. Open the volume valve in tranches — 10%, 50%, 100% over five business days.

Step 7 — Day-2 operations

• Daily — monitor AS4 send/receive metrics, alarm on rejection rate above the baseline.
• Weekly — sample-audit five invoices end-to-end (ERP → UBL → AP → MBS).
• Monthly — close-cycle reconciliation between ERP, AP outbound, and FIRS view.
• Quarterly — DR drill on the AP infrastructure.
• Annually — review of FIRS guidance and AP provider's certification status.

Cross-references

• Regulatory frame — FIRS e-invoicing Nigeria: Merchant-Buyer Solution explained.
• Multi-country context — e-invoicing mandates 2026 tracker.
• Multi-country roadmap — CTC mandates roadmap for multi-country businesses.

What we ship at GoRoute

GoRoute (POP000991) supports FIRS MBS issuance and reception out of the box. Nigerian customers go live in four to eight weeks on the standard runbook above. Book a demo.

Sources: FIRS public notices on MBS; OpenPeppol Service Provider directory; Peppol BIS Billing 3.0 specification.