How often must tachograph data be downloaded in Ireland?

In Ireland the driver card must be downloaded at least every 21 days, and the vehicle unit (VU) at least every 3 months (RSA/cvrt.ie). The downloaded data must then be kept for a minimum of 12 months. Many operators download more often to stay safely inside those limits.

The driver-card rule: every 21 days

Each driver’s smart card stores a rolling record of their driving, breaks and rest. Under the rules applied by the RSA, the data on a driver card must be downloaded at least once every 21 days. The clock runs from the last download, not from the calendar month, so a card downloaded on the 1st must be downloaded again by the 22nd.

The 21-day cycle matters because a driver card holds only a limited window of activity before the oldest days are overwritten. If you let a card run past 21 days you risk both a compliance breach and the permanent loss of records you are legally required to hold. Most well-run fleets treat 21 days as the outer limit and download cards on a shorter, fixed schedule (for example weekly) so a missed download never tips them over.

The vehicle-unit rule: every 3 months

The vehicle unit (VU) — the tachograph head fitted in the vehicle — keeps its own record of every journey, including periods driven by any card or with no card inserted. The VU must be downloaded at least every 3 months.

VU data is what lets you cross-check driver records against the vehicle itself and spot gaps such as unaccounted driving. Because it is collected far less frequently than the card, a single missed VU download leaves a much larger hole in your audit trail, so the 3-month deadline should be diarised per vehicle and never allowed to drift.

How long must you keep the data?

Once downloaded, tachograph data — both driver-card and VU files — must be retained for at least 12 months. In practice many operators keep it considerably longer to cover roadside inspections, audits and any infringement queries that surface after the fact.

Retention means more than leaving files on a laptop. The data should be stored securely, backed up, and readable on request. Losing files inside the 12-month window is itself a failure to comply, even where the original downloads were done on time.

What happens if you miss a download?

A missed or late download is a compliance failure that an RSA roadside or premises inspection can pick up. Tachograph and drivers’-hours offences can carry penalties of up to €5,000 and/or 6 months per offence, and both the driver and the operator can be held liable. The more practical risk for most fleets is the knock-on effect: overdue downloads raise your operator risk rating, which means more frequent inspections.

There is also the data-loss problem. Once a driver card is overwritten or a VU’s buffer rolls past the window, the missing records cannot be recovered — so a late download can leave a permanent, visible gap in your audit trail. The safest approach is to build in margin: download well before the 21-day and 3-month deadlines rather than on them.

Manual vs automatic (remote) download

You can meet these deadlines manually — physically inserting each driver card into a reader and plugging a download tool into each vehicle on a schedule. It works, but it depends on someone remembering, every card, every vehicle, every cycle, and it is easy for a single missed week to push a card past 21 days.

Automatic remote download removes that risk. The data is pulled over the air on a fixed schedule, well inside the 21-day and 3-month limits, stored centrally and retained automatically for the required period. For a multi-vehicle fleet it is the difference between hoping every deadline was met and being able to prove it.