Prepare your company to bid: AEAT certificates and Registro Mercantil

What you need to have ready

1. Cl@ve permanente or certificado digital de representante (FNMT).
2. Updated census data (Modelo 036/037) with the correct epígrafe IAE for the contract activity.
3. Escrituras and powers in case they check.
4. A quiet slot: some websites are flaky and sessions time out.

Documentation

• Certificado AEAT de estar al corriente para contratar (PDF with CSV).
• Certificación del Registro Mercantil of nombramiento y vigencia of the administrator and, if needed, the powers of the signer.
• Modelo 036/037 with the correct epígrafe IAE (proof of submission if you made changes).
• NIF and escritura de constitución (if the contracting body asks to verify objeto social).
• Certificado de titularidad bancaria for creditor registration (if required for payments).

Step by step

1. Hacienda (AEAT): go to sede.agenciatributaria.gob.es with Cl@ve/certificado and request the certificado de estar al corriente para contratar. Download the PDF with CSV.
2. Census/IAE: if the epígrafe doesn’t fit the contract, update the census with Modelo 036 on the AEAT Sede (section Censos, NIF, IVA). Keep the receipt.
3. Registro Mercantil: order on registradores.org a certificación of nombramiento y vigencia of the administrator (and powers if a proxy signs). Ask for electronic delivery with CSV so you can upload it as-is.
4. Digital certificate: if you don’t have one, request the representative certificate for a legal person at the FNMT and activate it. Many platforms won’t let you in without it.
5. Procurement platform: on contrataciondelestado.gob.es (or the platform the pliego specifies) prepare your bid. Authorise the contracting body to query data if the pliego allows; otherwise attach the certificates.
6. Corrections (subsanaciones): if requested, produce recent certificates (some pliegos limit to 3 months) and upload them within the deadline. Don’t argue about format: PDF with CSV is standard.

Time-saving tips

• Ask for everything electronically with CSV. Avoid scans that get rejected as “illegible”.
• Do the 036 before the tender. Last-minute IAE changes are a classic that leaves you out for timing reasons.
• Authorise the contracting body to query AEAT. Many already do this and you can skip attaching files.
• Have a clear power ‘to contract’. If the administrator delegates, grant an express power and record it in the RM.

Typical mistakes that can derail your application

1. Old certificates. The pliego asks for ‘recent’ and you upload one from 8 months ago: immediate exclusion.
2. Insufficient power. The signer lacks authority to contract/commit amounts: rejected on form.
3. IAE/objeto social mismatch. They deem you unfit and reject you.
4. Debt in AEAT executive collection. You can’t get the valid certificate and the tribunal won’t award you.
5. PDF without CSV or blurry scans. Not verifiable = inadmissible. Always request original electronic copies.