2027 accounting and tax calendar for a Luxembourg company

In short. A Luxembourg company tracks four families of deadlines in 2027: VAT (the 15th of the following month or quarter), annual accounts (approved within six months, filed with the RCS no later than 7 months after the close, meaning 31 July 2027 for a year ending 31 December 2026), corporate tax (the annual return plus quarterly advances due on the 10th), and activity-specific returns such as Intrastat. The 2027 budget cuts corporate tax by one point, which is one more reason to review your advances early in the year. Here is the calendar, month by month.

In Luxembourg, the hard part is never a single deadline. It is missing none of them while they pile up: VAT every month, payroll every month, annual accounts once a year, tax advances four times, and Intrastat for anyone above the thresholds. Here is the consolidated calendar for an SME in 2027, obligation by obligation and then month by month, with the exact dates and what a late filing costs. The 2026 edition is still available in our 2026 accounting and tax calendar; this version carries the 2027 dates and the effects of the new budget.

What changes in 2027 compared with 2026

The mechanics of the deadlines do not move from one year to the next: filing dates are set by law and stay stable. What changes in 2027 is the fiscal backdrop. The draft 2027 budget, tabled on 7 October 2026, lowers corporate income tax from 16 % to 15 %, removes the time limit on loss carry-forward, and raises the investment tax credit to 21 %. We cover these measures in our article on the 2027 Luxembourg budget. For the calendar, the practical point is simple: if your tax advances were set on the old rate, they tie up cash you will only recover at the final assessment. Early 2027 is the right moment to revise them.

VAT: the frequency follows your turnover

How often you file depends on your annual turnover excluding VAT. Three regimes coexist, with distinct deadlines (rules in force as of November 2026, source Guichet.lu).

Two points many owners mix up. There are in fact two separate annual returns: an annual VAT return, due by 1 March, and an annual recapitulative return that settles the year, due by 1 May of the following year. The latter is required even if you already file monthly or quarterly. On top of that comes the EC sales and services list, to be filed by the 25th of the following month or quarter as soon as you sell to business customers in other member states. Everything goes through the eCDF platform, and payment follows the same date as the return. The full mechanics are in our article on filing VAT in Luxembourg.

Annual accounts: the deadline that costs the most if you miss it

This is the most expensive thing to forget, because the surcharge is automatic. For a year ending 31 December 2026, the cycle runs as follows: the accounts are drawn up, approved by the general meeting within six months of the close (so by 30 June 2027 for most companies), validated on eCDF, then filed with the trade and companies register within the month after approval and no later than 7 months after the close, meaning 31 July 2027, per the Guichet.lu portal.

Past that seven-month deadline, increased filing fees apply in bands:

The preparation, the documents to gather and the eCDF-then-RCS sequence are described in our guide on filing annual accounts in Luxembourg.

Corporate tax: return and advances on the 10th

Your company owes corporate income tax (CIT), municipal business tax (MBT) and, where applicable, net wealth tax (NWT). Two kinds of deadline follow. First, the annual tax return, covering the previous year, due by 31 May; how it is calculated is set out in our article on corporate tax in Luxembourg. Second, the quarterly advances, called by the administration on the basis of your last known income and spread across the year:

The point to watch, sharper in 2027: advances are not optional, but they are adjustable. Ignoring them does not lower the final tax, it shifts the charge onto a heavier balance. Conversely, letting them run on a rate that is falling ties up cash. A short review early in the year with your account manager brings them back in line. The calculation and adjustment mechanics are detailed in our article on corporate tax advances in Luxembourg.

The returns that depend on your activity

Beyond the common core, some deadlines only concern part of the company population.

• Intrastat, if your trade in goods with the European Union passes the annual thresholds: 250,000 € on arrivals and 200,000 € on dispatches, each flow assessed separately. The return is then monthly, due by the 16th working day of the following month through IDEP.WEB, as our article on filing Intrastat in Luxembourg explains.
• Social declarations, if you employ staff: payroll generates monthly returns to the Joint Social Security Centre, with payment of contributions. From 1 January 2027 the minimum social wage rises, which changes your charges from the very first payroll of the year (see our article on the 2027 minimum social wage increase).

The 2027 calendar, month by month

Here are the consolidated markers for an SME whose financial year matches the calendar year, filing VAT quarterly, with employees. Adjust the VAT lines if you file monthly.

Monthly social declarations and the payment of contributions to the Joint Centre are not shown in this table, to keep it readable: they fall every month for any employer.

What has no date, but can land at any time

Two obligations are handled continuously, precisely because they have no fixed deadline. The FAIA file first: it is not filed on a date, but the administration can request it during an audit, and you then have to produce it quickly and correctly. The ten-year retention of documents second: a permanent obligation, whose weight you only feel the day you need to retrieve a document from year N-6. In both cases, books kept properly all year are the only real preparation.

How to stop chasing dates

The best way to manage a calendar is not to have to think about it. When the books are kept in real time, deadlines stop being end-of-period sprints: VAT is prepared from invoices already recorded, annual accounts start from a year closed month by month, and advances are provisioned as you go. That is the principle of our model. We keep your books in the Odoo we configure for Luxembourg, with deadlines tracked by your account manager, not left to your memory. The coupling between the management tool and the bookkeeping, described in our complete guide to accounting firms in Luxembourg, means every return flows from data that is already up to date.

Who this calendar is not enough for

This overview covers a standard Luxembourg SME whose financial year follows the calendar year. A holding company, an international structure, an offset financial year or an activity under special regimes (financial sector, complex VAT operations) have extra deadlines that go beyond this frame. Likewise, this calendar sets out the general rules in force as of November 2026 and the dates applicable in 2027; it does not replace a case-by-case check of your situation. When in doubt, a quick word with your account manager beats a fast read.

Frequently asked questions

What are the corporate tax advance dates in 2027?

Corporate income tax (CIT) advances are due on 10 March, 10 June, 10 September and 10 December. Municipal business tax and net wealth tax advances are due on 10 February, 10 May, 10 August and 10 November.

When must I file annual accounts for a year ending 31 December 2026?

Within the month after they are approved by the general meeting, and no later than 7 months after the close, meaning 31 July 2027, once validated on eCDF and filed with the trade and companies register. Past that, increased filing fees apply, from 50 € to 500 € depending on the delay.

What is the VAT filing deadline in Luxembourg?

The 15th of the following month for monthly returns, and the 15th of the month after the quarter (15 April, 15 July, 15 October, 15 January) for quarterly returns. On top of that, an annual return is due by 1 March and an annual recapitulative return by 1 May.

Does the 2027 budget change the deadlines?

No. The filing dates stay the same. The 2027 budget changes the rates instead, lowering corporate income tax from 16 % to 15 %. That is a reason to check your advances early in the year, so you do not tie up cash on a rate that has fallen.

Do I have to file an Intrastat return in 2027?

Only if your trade in goods with the European Union passes 250,000 € a year on arrivals or 200,000 € on dispatches, each flow assessed separately. Above that, the return is monthly, due by the 16th working day of the following month through IDEP.WEB.

Read more

• 2026 accounting and tax calendar for a Luxembourg company
• 2027 Luxembourg budget: what changes for SMEs
• Corporate tax advances in Luxembourg: dates, calculation and adjustment
• Filing annual accounts in Luxembourg: deadlines and surcharges
• Accounting firm in Luxembourg: the complete guide for an SME

Why Advena?

We are the Luxembourg accounting firm that keeps your books inside the management tool it deployed for you. Your deadlines are tracked by a dedicated account manager, from books that stay permanently up to date, for a closed fixed fee from 325 € a month, annual accounts and RCS filing included. Our model is built for SMEs of 1 to 50 employees; for a complex holding or a multi-jurisdiction structure, we will tell you plainly. We inform and we point the way, we do not replace tailored tax advice.

Information current as of 13 November 2026, based on the rules in force (Guichet.lu tax calendar) and the draft 2027 budget. Filing dates are set by law; the 2027 budget measures remain subject to the vote. This article is for information and does not constitute tailored tax advice.