New Model 185 (2026): A Revolution in Reporting Social Security Contributions by Members and Mutual Society Members

Introduction

In Spanish taxation and the tax monitoring of social security contributions, it is important to understand the recent approval of the new information return, Model 185 — “Monthly information return on contributions by Social Security members and mutual society members” — under Order HAC/1197/2025 of 21 October 2025. This regulatory change represents a significant modernisation of the system through which Social Security managing bodies and alternative mutual societies provide data, moving towards large-scale data processing and automation instead of the previous manual system. Order HAC/1197/2025

As with other innovations in tax and contribution rules, both the operational aspects and the tax consequences should be analysed so that reporting entities can be properly advised and the challenges and opportunities created by the new obligation anticipated.

---

What is Model 185 and who is affected?

Order HAC/1197/2025 approves Model 185, the “Monthly information return on contributions by Social Security members and mutual society members,” and sets out its purpose, scope, filing deadlines and procedure. Official text in the BOE

Entities required to file:

• The bodies or entities that manage Social Security, including special schemes (civil servants, the Armed Forces and staff serving the Administration of Justice).
• Mutual societies that operate as alternatives to Social Security.

Frequency and format:

• The return must be filed monthly.
• Deadline: within the ten calendar days following the end of the month covered by the return.
• Format: electronic only.

Entry into force:

• The rules entered into force on 1 January 2026.
• They first apply to returns for January 2026, which must be filed in February 2026.
• For monthly returns for 2026 and later years, Order HAC/96/2003 of 28 January is repealed.

Spanish Tax Agency announcement on Model 185

---

What changes compared with the previous model?

The change is substantial. This is not simply a new form number, but a structural transformation in the way data is supplied and processed:

1. Data submission: The previous Order HAC/96/2003 was designed for computer-readable media and introduced a manual online filing system (“teleprocessing”) that required subsequent manual processing by the administration.
2. New transmission technology: Order HAC/1197/2025 requires information to be submitted using the standards for large volumes of information (TGVI online). This allows data to be validated as it is received, reduces manual errors and automates large-scale processing.
3. Improved quality and reliability: Under the new system, the Spanish Tax Agency (AEAT) will receive more reliable data with less delay. This directly affects the administration of tax deductions linked to social security contributions, as discussed below.
4. Electronic-only format: Model 185 is electronic from the outset, requiring reporting entities to adapt their technology and procedures.

In short, the manual reporting model is being replaced by large-scale, automated data flows. Tax advisers should encourage Social Security managing bodies and mutual societies to begin the necessary technological and organisational adjustments as soon as possible.

---

Why was the new model approved? What is it intended to achieve?

The rules do more than amend a formal filing obligation. They reflect tax policy and the monitoring of deductions, with practical consequences for taxpayers. The main objectives include:

• Ensuring the proper administration of the maternity deduction and deductions for large families or dependants with disabilities. Under Articles 81 and 81 bis of Law 35/2006, these deductions require the taxpayer to be registered with Social Security or a mutual society and to have contributed for a minimum period. The new reporting obligation makes it easier to verify those requirements.
• Enabling these personal income tax deductions to be paid monthly in advance. Better monthly contribution data allows the AEAT to administer advance payments more accurately.
• Improving tax administration and oversight through more reliable, automated monthly data, reducing errors, fraud and discrepancies in deductions linked to employment. Taxpayers may also benefit because the AEAT will work with more up-to-date and verified information.

Overall, the new model is a strategic part of the tax-control system for social security contributions, with direct effects on the deductions system.

---

Implications for managing bodies

Social security contribution managing bodies and the teams that work with them should consider several points:

1. Technological and organisational adaptation: Reporting entities need systems capable of generating files in line with the logical designs in the order’s annex. This involves large-scale processing, TGVI transmission and automated validation. They should check whether their member information systems can provide the required level of detail, including registrations, deregistrations, scheme, membership number and monthly contributions accrued.
2. Review of internal processes: Because the filing deadline is short—ten calendar days after month-end—internal information must be checked and reconciled, significant delays avoided, and data integration between Social Security or the mutual society and the filing system aligned.
3. Effect on taxpayers’ deductions: Clients should be told that, from 2026, the AEAT will have monthly contribution information that it can compare with personal income tax returns and claims for the maternity, large-family or dependant-disability deductions. An error in reporting or contributions may affect eligibility or advance payment of a deduction.
4. Advance planning: Although the rules apply from January 2026, managing bodies and advisers should prepare a transition plan with milestones, filing tests, data-integrity checks and quality controls to prevent penalties or problems.
5. Training and communication: This technological and organisational change requires the relevant departments (IT, accounting, Social Security relations and tax advice) to be informed and trained.

---

Potential challenges and key issues

As with any significant regulatory change, there are risks and uncertainties that should be monitored:

• Quality of membership and accrued contribution data: If internal information is not consistent, the AEAT’s validation system may identify discrepancies. Rejected files or requests for correction may arise.
• Filing within the required deadline: The new deadline—10 calendar days after each month—may be demanding for entities with large numbers of members. Processes will need to be automated as far as possible to avoid filing issues.
• Technical compatibility and standardisation of files: The logical designs are included in the order’s annex. Entities must update their systems to generate files in the exact required format; any deviation may lead to rejection.
• Integration with deductions and advance payments: Unreliable or delayed contribution information may adversely affect deduction calculations or advance payments, potentially leading to AEAT claims or later adjustments.
• Penalties or consequences for non-compliant entities: If a reporting entity fails to submit Model 185 when required, this may be treated as a failure to cooperate and could lead to penalties for information-reporting breaches or correction requirements that delay tax administration.

---

Conclusion and final recommendations

Approval of the new Model 185 under Order HAC/1197/2025 is a key measure in Spanish tax policy. It initiates a transition to large-scale, automated monthly data reporting on social security contributions. Managing bodies face an immediate need to adapt their technology and organisation, even though the new system’s operational application begins in January 2026.

Read the original article in Spanish.