Tax Adviser in Bilbao: Bizkaia Foral Regime and Economic Agreement for Companies

Bilbao and Greater Bilbao operate under Spain's most distinctive tax system: the Bizkaia foral regime, underpinned by the Economic Agreement between the State and the Basque Country (Law 12/2002). Under the Agreement, the Diputación Foral de Bizkaia has normative and revenue powers over the main direct taxes — the foral Corporate Income Tax (governed by Foral Regulation 11/2013) and the foral IRPF (Foral Regulation 13/2013) — with its own rates, deductions, and application criteria that differ materially from common territory legislation. A company based in Bilbao applying state legislation without adapting its management to foral rules is, in all likelihood, filing incorrectly and paying more tax than necessary.

The Bizkaia Foral Regime: Why It Is Different and Why It Matters for Your Company

The Economic Agreement is not a historical curiosity: it is the legal framework that determines that companies with their registered office in Bizkaia pay CIT and IRPF under legislation issued by the Diputación Foral de Bizkaia, not under Law 27/2014 or Law 35/2006. The differences are material and have direct economic implications.

The general rate of the Bizkaia foral CIT is 24%, versus 25% in common territory. Micro-businesses — companies with turnover below EUR 2 million and an average workforce below 10 — pay at 20%. Beyond rates, the most important differences are in the deductions: the Bizkaia foral CIT includes deductions for productive asset investment, job creation for hard-to-employ groups, R&D activity participation, and certain environmental investments that have no exact equivalent in state legislation.

Correct application of the Economic Agreement also requires determining, in each case, which administration is competent — Hacienda Foral de Bizkaia or AEAT — and in what proportion. This is done through the connection-point rules: registered office, volume of operations in each territory, and the nature of the activity.

Hybrid Model: BMC Team + Local Member in Bilbao

BMC serves clients in Bilbao and Bizkaia through a remote advisory model combining the Madrid tax team — with proven expertise in the foral regime and Economic Agreement connection points — with the in-person support of D. Iñaki Etxeberria Arana (Economist, Member No. 04.XXX, Colegio Vasco de Economistas). This structure delivers technically rigorous foral advice without the cost of a local Basque Country office, with availability for in-person proceedings when required.

What Our Tax Advisory Service in Bilbao Includes

Foral tax compliance: foral CIT (Foral Regulation 11/2013), foral VAT, foral IRPF withholdings, Wealth Tax, and all foral informative returns.

Strategic foral planning: optimisation of the effective foral CIT rate through the correct application of specific deductions, family business planning under foral legislation, and structuring of groups with activity in Bizkaia and common territory.

Defence before Hacienda Foral and TEAF: representation in Hacienda Foral de Bizkaia audit and inspection proceedings, claims before the TEAF de Bizkaia, and contentious-administrative appeals before the TSJ of the Basque Country.

International tax: transfer pricing for Basque groups with foreign subsidiaries, double taxation treaty application, and related-party transaction documentation under foral legislation.

Request a consultation with our team. Free of charge and with no commitment, we analyse whether your company is correctly taxed under the Bizkaia foral regime and identify the optimisation opportunities and risks to be managed as a priority.