ERP e-invoicing in the UK: SAP, Oracle, Dynamics, NetSuite

If you run SAP, Oracle, Microsoft Dynamics, NetSuite or another ERP, UK e-invoicing is an integration project: your ERP must turn VAT invoices into Peppol e-invoices, hand them to an Access Point, and import supplier e-invoices into accounts payable, ready for April 2029. Whether that is a configuration change or a significant build depends on your ERP version, add-ons and how many invoicing systems you have.

This guide does not assess any vendor's product. Capabilities vary by edition, version, region and licence, and change frequently. Instead, it sets out the options, the questions to put to your vendor or partner, and the risks we see in ERP projects.

What is confirmed

• E-invoicing is mandatory for VAT invoices from April 2029 (government consultation response).
• Decentralised model, with invoices exchanged between businesses through service providers.
• Peppol is the network. The GOV.UK Tax update 2026 summary says: "The government has announced that the electronic procurement system Peppol will be the core interoperability network for e-invoicing in the UK." The same document says the government will keep engaging on "the role of legacy systems which cannot interoperate in the future system".
• No real-time reporting to HMRC alongside the mandate.

Not yet confirmed: the final data standard. The consultation response says the government will review "the risks and benefits of adopting an existing standard or designing a UK-specific standard". Today's reference point is Peppol BIS Billing 3.0, built on EN 16931. Any UK-specific rules (a CIUS) would affect your mappings. The roadmap is due at Budget 2026 on 28 October 2026.

Three ways to connect an ERP to Peppol

Option	How it works	Suits	Watch out for
Native ERP feature	The ERP vendor's own e-invoicing or e-document module creates and sends documents, sometimes via a vendor-run or partner service	Businesses on current versions of the ERP	Licence cost, UK coverage, version upgrades required
Add-on or partner connector	A certified add-on maps ERP data to Peppol and connects to an Access Point	Older versions, or where native UK support is not ready	Support model, upgrade compatibility
Separate Access Point or integration platform	The ERP exports invoice data (via API or file); a provider converts, validates and sends	Several ERPs, billing systems or countries	Mapping ownership, two-way status flow, data duplication

Many groups end up with a mix: the main ERP connected one way, and smaller billing systems another. A single Peppol connection for the whole group, fed from several systems, can be simpler to run.

Questions to put to your ERP vendor or partner

Ask in writing and ask for the documentation reference:

1. For our exact product, edition and version, is UK Peppol sending supported today? Receiving?
2. Are invoices and credit notes supported, including self-billed invoices if we use them?
3. Is a version upgrade or new licence required?
4. Which Access Point is used? Is it on the OpenPeppol list of certified service providers?
5. How will you implement UK-specific rules once the specification is published, and how quickly?
6. How are Peppol validation errors shown, and to whom?
7. Can incoming e-invoices be matched to purchase orders and goods receipts automatically?
8. Are Peppol invoice responses supported in both directions?
9. How are attachments stored and archived with the invoice?
10. Is there a test environment, and can we test with real trading partners?

Our guide to checking Peppol support explains how to judge the answers.

ERP data mapping: where projects slip

ERP projects rarely fail on the connection; they slip on data. Map each Peppol BIS Billing 3.0 field to an ERP source early:

• Parties: legal entity name, address, VAT number and Peppol ID for every company code or business unit.
• Tax: each ERP tax code to a VAT category code and rate, including reverse charge and exempt codes.
• References: PO number and buyer reference (BT-10), contract and delivery references.
• Units of measure: ERP units to the code lists Peppol uses.
• Rounding: line and document totals calculated the way Peppol rules expect. Rounding is behind errors such as BR-CO-15.
• Currency: foreign currency invoices still need VAT totals in sterling under HMRC rules. See multi-currency e-invoices.

A suggested phased plan for ERP users

Phase	Activities
1. Discovery (now)	Inventory invoicing systems and volumes; ask vendors the questions above
2. Design	Choose connection option; map data; design exception handling
3. Wait for spec	Confirm UK rules from the roadmap and guidance; adjust mappings
4. Build and test	Configure, integrate, test with partners already on Peppol
5. Pilot	Go live with a subset of customers and suppliers
6. Roll-out	Extend to all in-scope entities before April 2029

Phases 1 and 2 can start now. See the full e-invoicing project plan.

Legacy systems

If part of your estate cannot produce structured invoices, raise it now. The government has said it will continue to engage on legacy systems that cannot interoperate in the future system, but has not said what any accommodation would be. Plan on the basis that you will need to replace or wrap them.

What to do now

• List every system that creates VAT invoices, by legal entity.
• Send the ten questions above to your ERP vendor or partner.
• Start the tax code and party data mapping.
• Budget for licences, integration, testing and partner onboarding (see e-invoicing costs).
• Work through the readiness checklist.