How Accurate Are Spain's Speed Cameras? DGT Radar Margins Explained (2026)
A radar reading is not a raw number, it is a number with a legally fixed margin of error already built in. Spain regulates exactly how accurate a speed camera has to be, and the answer depends on whether the unit is fixed or mobile, and whether it was just type-approved or has been running in service for years. This page sets out the actual figures and where they matter.
Information last verified on 23 July 2026. This page provides general legal information about Spanish law and does not constitute legal advice in an individual case.
Where the margin comes from
Orden ICT/155/2020 regulates the state's metrological control of measuring instruments, and its Anexo XII covers cinemómetros, the technical name for speed-measuring radar. Two different margins apply depending on the instrument's stage of life: one at type-approval, when a new model is first certified (evaluación de la conformidad), and a looser one at periodic re-verification, once a unit is already deployed and checked on a recurring schedule (verificación periódica). Both figures differ again between fixed and mobile installations.
The actual numbers
| Instrument | New / type-approved | In service (periodic check) |
|---|---|---|
| Fixed or static, up to 100 km/h | ±3 km/h | ±5 km/h |
| Fixed or static, above 100 km/h | ±3 % | ±5 % |
| Mobile (vehicle-mounted), up to 100 km/h | ±5 km/h | ±7 km/h |
| Mobile (vehicle-mounted), above 100 km/h | ±5 % | ±7 % |
The pattern is consistent in both directions: fixed cameras are held to tighter margins than mobile ones, and a freshly certified instrument is held to a tighter margin than the same instrument once it has been running in service for a while.
Type-approval testing itself happens in two stages, and the figures above are the road-traffic ones, the numbers that actually apply once a unit is deployed. In laboratory simulation, before a model ever reaches the road, the certification margin is tighter still, ±2 km/h for fixed instruments and ±1 km/h for mobile ones. That gap between the laboratory figure and the road figure is a reminder that the numbers in the table are not a loophole built into the law; they are what remains after certification testing already pushed the margin as tight as real traffic conditions allow.
The Orden's general rule for how the margin has to be applied is explicit: the instrument «no explotará el error máximo permitido ni favorecerá sistemáticamente a ninguna de las partes», meaning the margin is meant to sit neutrally, not be used to squeeze the reading against the driver. In practice, that means the figure cited against a driver should already have the applicable margin subtracted before it is used as evidence.
Section-average and aircraft-based controls
Two other measurement types exist alongside ordinary point radar. Cinemómetros de tramo measure a vehicle's average speed across a stretch of road rather than at a single point, and radar can also be operated from an aircraft. For both of these, Anexo XII does not loosen the margin at periodic re-verification the way it does for fixed and mobile point radar: the same tighter figures used at type-approval keep applying for as long as the instrument is in service. A tramo or aerial reading is therefore always held to the stricter new-instrument standard, never the looser one.
After a repair
A radar that has been repaired or modified does not simply return to its looser in-service margin. Anexo XII requires it to be re-verified against the new-instrument margins, the tighter figures in the table above, not the periodic-check ones. A ticket generated soon after a unit's known repair or recalibration is worth checking against which set of margins actually applied that day.
No verified 2025 or 2026 change
These margins trace to a single instrument, Orden ICT/155/2020, and nothing in that Orden's current, in-force text shows a revision for 2025 or 2026. Claims of a recent margin change circulate online, but the figures above remain the legal standard as of the last check of the primary text.
Using the margin in an appeal
A margin of error is not proof a ticket is wrong; radars are certified and checked precisely so that their readings, margin included, hold up. But a measurement that sits right at the edge of a fine or points band is worth a second look, since the margin can be the difference between one band on the speeding table and the next, or between an infraction and none at all. Raising the instrument's margin of error is a legitimate argument inside the alegaciones window covered on the appeals page.
The wider map of Spanish traffic law, including the full fine and appeal process, is on the multas page and the driving section.
This page is general legal information about Spanish law and does not constitute legal advice in an individual case. The controlling texts are the current versions in the BOE and the DGT's official pages.
Frequently Asked Questions
How accurate are Spain's DGT speed cameras?
It depends on the type and status of the unit. A new fixed camera is accurate to within ±3 km/h (or 3 percent above 100 km/h); once in service, that widens to ±5 km/h or 5 percent. Mobile radar is looser still: ±5 km/h or 5 percent new, ±7 km/h or 7 percent in service.
Is a mobile radar van less accurate than a fixed speed camera?
Yes. Mobile, vehicle-mounted radar carries looser legal margins than fixed cameras at every stage of its life, under Orden ICT/155/2020, Anexo XII.
Does a radar's margin of error get applied automatically, or do I have to ask?
By regulation, the margin has to be applied neutrally before a reading is used as evidence. In practice, a driver disputing a borderline reading can still raise the applicable margin as an argument in the alegaciones stage of an appeal.
Have Spain's radar margins changed recently?
Not according to the current, in-force text of Orden ICT/155/2020, the instrument that sets them. The figures for fixed and mobile radar, new and in-service, remain those set out in that Orden.