ERP Implementation Consultant, Spain

Why Spanish go-lives get noisy in the first weeks

Most Spanish implementations I review did not fail in design. They became painful in the first weeks live because a handful of outward-facing flows had never been run end to end. The usual suspects:

• Invoice records rejected by the tax agency. SII submissions were tested with a few clean invoices, not with credit notes, simplified invoices or customers with incomplete tax IDs.
• Invoice series that break continuity. The new system starts a series that overlaps with the old one, or corrective invoices cannot reference invoices issued before go-live.
• Remittance files the bank does not accept. SEPA direct debit files were generated but never sent to the actual bank.
• Payroll entries that stop importing. The gestoría's file format no longer matches the new chart of accounts or cost centers.
• Regional entities left until last. The Canary Islands or Basque company is configured after the main entity, with little time to test.

All of these can be caught before go-live if someone on the company side insists on seeing them work. That is my role, building on the requirements and scenarios from the selection stage in Spain or, if you skipped it, on a short review of your contract and scope.

Working beside the integrator: who does what

Confusion about responsibilities causes more friction than technical problems do. At the start of each engagement I agree a simple split with your integrator and management, and it usually looks like this:

With the split written down, I run a weekly session with the integrator's project manager and a steering meeting with management. Decisions, risks and change requests sit in shared logs with named owners. I do not configure the system on integrator-led projects or take over the integrator's responsibility; I keep the company's side organized and its decisions on time. The broader method is set out on my ERP implementation page.

Moving data out of Sage, a3, Holded and spreadsheets

Spanish companies typically migrate from a desktop or cloud package such as Sage, an a3 product, Holded or an older ContaPlus installation, with spreadsheets covering stock, projects or commissions. The integrator supplies templates and loads the data; the company has to clean it and prove it is right.

I organize the checks around the records that cause the most trouble when wrong:

• Customers and suppliers with valid tax IDs, addresses and the territory that decides their tax treatment.
• Bank accounts and SEPA mandates for customers paying by direct debit, so the first remittance after go-live is accepted.
• Open receivables and payables, including partially paid invoices and pending remittances.
• The last invoice number in each series, so numbering continues correctly in the new system.
• Opening balances by account and stock values by warehouse, agreed to the legacy figures.

A trial load passes only when the data owner has compared totals and signed them off. Corrections happen in the source or the mapping rules. Your advisor confirms how long older records must remain accessible and where they will be kept. The detailed approach is on my ERP data migration page and in the migration checklist.

Rehearsing SII, invoice series and remittances

Acceptance testing in Spain should prove the flows that the tax agency, banks and customers will see. With your department heads I write scenarios that cover:

1. A sales cycle ending in an invoice, a partial corrective invoice and the resulting SII records, checked in the integrator's test setup and, where available, the tax agency's test environment.
2. An invoice issued in the old system and corrected in the new one, to prove references across the switch.
3. A SEPA direct debit remittance sent to each bank you use, followed by a returned debit and its charges.
4. A confirming or transfer payment run to suppliers.
5. An intra-EU sale and, where relevant, transactions from Canary Islands or Basque entities.
6. A monthly close producing the reports your asesor fiscal uses for returns.

Your asesor fiscal reviews the tax outputs; I check that the scenarios use realistic data and that results are recorded. Defects go into one list, reviewed with the integrator and sorted into real faults, gaps in user knowledge and fresh requests. Testing closes once the sign-off criteria set before it started are satisfied, not when the calendar says so. The full method is under ERP testing and UAT.

Cutover timing, the payroll file and hypercare

The choice of switch-over point is made with your asesor fiscal and finance lead. Most companies prefer to change after a period-end so a tax return does not draw on two systems, and the old system stays readable for the records you must keep. The runbook then lists every step with an owner: freezing the old system, final loads, opening new invoice series, switching bank files, enabling users and confirming the first invoices and remittances.

Payroll usually stays with the gestoría or a payroll provider. Before go-live I make sure their file maps to the new accounts and cost centers, that someone is named to import it and that a reconciliation step exists each month. The same applies to any other file your advisors send or receive.

Hypercare starts with the first invoices. Key users meet briefly each day to work through one issue list, anything blocking invoicing, shipping or collections is handled first, and configuration faults go to the integrator. Support scales down once the first monthly close is complete and the exit conditions are met. I run this remotely, with key users helping colleagues at each site; a visit can be arranged if needed. More on my work with Spanish companies is on the Spain overview and the Spanish ERP consultant page.