Luxembourg employers must file 2026 salary statements in new XSD v1.0 format

Every Luxembourg employer and pension fund that paid salaries, pensions or annuities during 2026 must transmit the annual Extraits de compte salaire et pension (ECSP) to the Administration des contributions directes (ACD)Public in the dedicated 2026 format: an XML file conforming to XSD version 1.0Public, filed under démarche code ACD_DEPOT_ECSP_2026PublicPublic. The 2026 package comprises the XSD file, a descriptive integrator document and the ECSP Tutoriel Année 2026. Filings covering fiscal year 2026 must reach the ACD before 1 March 2027Public, the general rule being transmission before 1 March of the year following the tax yearPublic.

Filing is electronic only, through MyGuichet.lu, either the citizen or the business portalPublic. The declarant either uploads a structured XML file of at most 7 MB or uses the online input assistant. Filing may be entrusted to an intermediary acting for the employer or pension fund, such as a mandataire or fiduciaire. In both channels, identification of the declarant requires an accepted LuxTrust product, private or pro.Public National identification numbers must be entered without spaces: the 13-digit national identifier for natural persons and the 11-digit identifier for legal persons.

Each electronic extract must cover all salaries and pensions the employer or pension fund paid during the tax year to the account holder, and a separate extract must be drawn up for each country of residence of the employee or pensioner. Paper returns to the ACD, formerly attached as certificats de salaire ou de pension to the back of the original fiches de retenue d'impôt, are no longer acceptedPublic. The former employer obligation to draw up a décompte annuel has been abolished with effect from tax year 2014.

Employers and pension funds keep the original fiches de retenue d'impôt for ten years under the rules applicable to commercial documents and no longer return them to the ACD. They must still hand each employee or pensioner an annual paper certificat de salaire ou de pension drawn from the online specimens modèle 160 and modèle 170. Where the beneficiary's tax class or address changed during the year, a single paper certificate suffices, showing the last valid tax class for the tax year concerned and the most recent address.

Software editors and IT providers can pre-validate generated XML on the ACD pre-validation platform before filing live data through MyGuichet.lu; access to the test platform accepts LuxTrust or a username and password, while the final filing with real data requires LuxTrustPublic. Semantic checks on the test platform are not identical to the live validation, notably for national identification numbers, and only fictitious data may be uploaded there. Employers of domestic staff taxed under the régime d'imposition forfaitaire do not file themselvesPublic: the Centre commun de la sécurité sociale (CCSS) transmits the ECSP on their behalfPublic.

Legal basis: loi du 26 mars 2014 transposing Article 8 of Council Directive 2011/16/EU on administrative cooperation in the field of taxation, and the ACD ECSP transmission rules including the 1 March filing deadline and the 2026 XSD format.