Filing tax and VAT returns in Luxembourg through eCDF and MyGuichet

VAT returns and annual accounts go through eCDF, and the personal LuxTrust app will not do it — filing requires a LuxTrust Pro certificate starting at €130. Once validated there, those annual accounts are available to the AED and the ACD to cross-check against your VAT and corporate tax returns.

Founders often assume the State operates a central portal for corporate compliance. It operates parallel systems that handle distinct declarations, read different credentials, and enforce their own deadlines.

The State splits the filings across distinct platforms

The platforms divide the accounting year from the tax year. The platform's objective specifies that eCDF, the State's electronic platform for collecting financial data, is run by the CTIE; companies prepare, validate and transmit periodic and annual declarations, annual accounts and the standard chart of accounts through it according to the platform's published scope. The rule is absolute: the mandate dictates that since 1 January 2020 every VAT return — monthly, quarterly or annual — must be filed electronically through eCDF, as an online form or an XML file under the rules for taxable persons.

Corporate income tax goes through a separate channel. Filing is mandatory via MyGuichet.lu since tax year 2017 for resident capital companies, including the s.à r.l. and the s.à r.l.-S on the tax administration's portal. That platform receives a single return (modèle 500) covering corporate income tax, municipal business tax and net wealth tax.

In practice, filings reach eCDF either as XML files generated by accounting software against the CTIE's predefined structure, or typed and validated in the on-screen forms. When an external firm keeps the books as part of accounting and tax administration, they generate the XML directly from the ledger to avoid manual entry errors.

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The entities outside the mandatory electronic filing scope

The obligation to file electronically does not apply universally to every structure registered in the country. Because the rule explicitly states that electronic filing is mandatory via MyGuichet.lu since tax year 2017 for resident capital companies, other legal forms fall outside this specific strict mandate. Partnerships, sole traders, and non-resident entities are not caught by the exact wording of the resident capital company requirement, leaving those outside the scope to rely on traditional submission methods.

Professional hardware is required to sign the return

Accessing these portals and signing the submissions requires specific authentication. To access the corporate tax portal, a LuxTrust product (private or pro) is required both to use MyGuichet and to sign the return. The standard personal application costs €115 and remains valid for 3 years. The full package for the personal application costs €115 for 3 years (LuxTrust App, video identification, active ≤ ~48h).

However, the filings on eCDF demand professional hardware. A LuxTrust Pro device is required, with the base "Scan" reader starting at €130 directly from the issuer. The standard SmartCard costs €160, while the expedited card costs €320. Every professional product in the range is valid for 3 years.

The authentication requirements for the corporate space

Setting up the workspace on MyGuichet requires a specific credential. To create the space, the founder needs a private or professional LuxTrust product, a Luxembourg electronic identity card, or an eIDAS device from another European country, along with the company's 13-digit matricule. The space itself is collaborative — the administrator can invite other people to join the eSpace and handle procedures inside it. It covers legal persons, the self-employed and associations.

The limits of what the administration publishes

While the statutory deadlines for the company are strictly enforced, the reciprocal timeline from the State remains unpublished. Luxembourg publishes very little about how fast it will work, and a great deal about how fast you must. What remains unknown is the exact processing time for a submitted return or the internal metrics that trigger a VAT audit. The founder is held to a hard calendar, while the administration operates on its own unstated schedule.

The retention rules that outlast the active business

The cycle runs on strict statutory dates, and the penalty for missing them scales with the delay. The bookkeeping requirements in Luxembourg mandate that all supporting documents remain available for 10 years in Luxembourg. This duty survives the active trading life of the company; records of a company in liquidation must be kept for 5 years. The administration expects the ledger and the documents behind it to remain accessible long after the financial year has closed.

The cycle enforces separate deadlines for tax and accounts

The divided sequence for annual accounts

The outer accounts deadline is a divided sequence. The general assembly must approve the accounts within 6 months of the financial year-end. Filing with the RCS then runs for 1 month, creating the strict 7-month final limit.

Cross-border trading creates an additional reporting duty

Companies trading across borders carry an external reporting duty. Under this framework, the rule states that businesses subject to Luxembourg VAT declare goods delivered and services provided to professionals in other EU member states to the AED, in addition to their VAT return. These filings track the physical and digital export of value, and they must align perfectly with the revenue declared in the main VAT return.

The timeline for the corporate tax declarations

The corporate income tax cycle operates on a longer calendar than the periodic VAT returns. The statutory cutoff is 31 December of the year following the tax year (CIT and municipal business tax returns, since tax year 2022) according to the ACD. Missing this outer limit exposes the company to the financial penalties detailed below, regardless of whether the annual accounts have been successfully deposited at the RCS.

The reconciliation checklist for annual filings

Before the final submissions are locked, the turnover figures must be reconciled across three distinct documents. The turnover recorded in the profit and loss account must be checked against the turnover declared for VAT, and both must be checked against the turnover in the modèle 500. While the administration's published guidance does not exhaustively list the legitimate reasons these three differ, the tax office expects the company to be able to explain any variance immediately upon request.

The authorities read your filings against each other

The State does not treat these submissions in isolation. Instead, annual accounts validated in eCDF serve the official RCS filing and are available to STATEC for statistics and to the AED and ACD for cross-checking annual VAT and tax returns.

This means the turnover recorded in the profit and loss account, the turnover declared on the periodic VAT returns, and the final taxable basis submitted in the corporate tax return are fully visible to the respective administrations. Any mismatch across the portals invites immediate scrutiny.

Failing to reconcile those figures before submission carries escalating costs. Breaching the VAT obligations triggers fines that range from €250 to €10,000. On the direct tax side, filing the corporate return past the deadline or with unresolved discrepancies allows the ACD to apply the late filing supplement of up to 10% of the final tax due. The administration trusts the data exactly as far as the underlying systems align.

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Figures verified against ecdf.b2g.etat.lu, guichet.public.lu, impotsdirects.public.lu, luxtrust.com, guichet.public.lu, guichet.public.lu, guichet.public.lu, impotsdirects.public.lu on 2026-10-16.