How to pass the MOT for trailers the first time: a guide for light, heavy, and agricultural trailers

Approximately one in five trailers fail their first ITV (vehicle inspection) attempt, according to reports from major authorized stations in Spain. The causes are almost always the same: maladjusted brakes, burnt-out lights, or forgetting hitch ball documentation at home. Avoidable errors that result in double fees and a lost month until the next appointment.

This guide addresses each step of the process with updated data: which trailers need to pass the ITV, how often, what documents to bring, what exactly is inspected, and what to do if you fail. It's designed to ensure you arrive at the station with everything in order and leave with a stamped certificate.

We have been manufacturing and selling approved trailers throughout Spain for fifteen years. The trailers we sell pass the ITV first time because they leave the factory with hot-dip galvanization, an approved inertia brake, and complete documentation. But even a perfect trailer needs a pre-inspection checklist. That's what you'll find here.

Which trailers need to pass the ITV?

All trailers with a maximum authorized mass (MMA) exceeding 750 kg must pass the ITV. Light trailers (MMA ≤ 750 kg) are exempt from periodic inspection, although they must accompany the towing vehicle when it undergoes its own ITV and keep their documentation up to date.

Here is a quick overview by trailer type:

This classification comes from Royal Decree 920/2017 and the General Vehicle Regulation (Royal Decree 2822/1998), supplemented with technical documentation published by TÜV Rheinland and Mapfre.

Exact deadlines: how often each type of trailer passes the ITV

The deadlines change according to the age of the trailer, not just the type. Here is the complete updated table:

Heavy trailers (MMA exceeding 750 kg)

The count starts from the trailer's first registration date, not from the purchase or the previous ITV. Check this information on the circulation permit before making an appointment.

Caravans and motorhomes

Caravans with an MMA exceeding 750 kg undergo their first ITV at 6 years from registration and then every 2 years. Motorhomes follow car deadlines: first ITV at 4 years, biennial until 10 years, and annual thereafter.

Agricultural trailers

Agricultural trailers are subject to regional regulations. The usual frequency is every 2 years for trailers with an MMA exceeding 750 kg, but some autonomous communities (Catalonia, Aragon, Castilla y León) apply specific conditions. Always confirm at the nearest station.

Light trailers (MMA ≤ 750 kg)

They do not undergo periodic inspection. However, they must physically attend the ITV station with the towing car when it undergoes its own inspection. Inspectors check that the hitch is approved, that the lights connect correctly, and that the documentation is complete.

Mandatory documentation for your trailer's ITV

Forgetting a document is the number one cause of missed appointments at the first ITV. The complete list is:

• Technical inspection card (ITV card) of the trailer.

• Circulation permit of the trailer.

• Valid insurance: included in the car's policy for light trailers; separate and mandatory policy for heavy trailers.

• Hitch ball approval certificate (manufacturer's conformity report).

• Invoice or installation certificate of the hitch, issued by a workshop recognized by Industry.

• DNI of the owner or authorization if presented by another person.

If it's the trailer's first ITV after a modification (axle change, load capacity expansion, brake installation), add the modification certificate signed by a competent engineer. Without it, the inspection will not yield a favorable result.

Pre-ITV Checklist: what to check before taking your trailer to the ITV

This is the list our customers ask us for via message every week. Review it 24 hours before your appointment.

Trailer identification

• License plate clean and legible (red for heavy trailers, white with car license plate for light ones).

• Visible VIN (not rusty or covered by stickers).

• Valid ITV card without alterations.

Lighting and signaling

• Brake lights working on both sides.

• Turn signals working on both sides.

• Rear position lights (red) and front position lights (where applicable).

• Rear triangular reflectors intact.

• Electrical connector (7 or 13 pins) without oxidation, all wires making contact.

Brakes (for heavy trailers only)

• Inertia brake with the drawbar moving smoothly when dry (no oxidation blocking the actuator).

• Discs and pads without visible cracks.

• Safety cable correctly anchored to the car.

• Manually check braking by pulling the trailer backward: the wheels should resist before locking.

Structure and suspension

• Chassis without cracks in welds (check after winter storage in humid areas).

• Leaf springs or coil springs without abnormal play.

• Hitch ball without visible wear (nominal size 50 mm).

• Straps or load securing systems in good condition.

Tires

• Minimum tread depth of 1.6 mm (2 mm recommended for inspection).

• Correct pressure according to the technical data sheet (usually between 2.5 and 4 bar).

• No cracks on sidewalls or deformations.

• Exact dimension matching that indicated on the trailer's technical data sheet.

Specific for boat trailers

• Hot-dip galvanized frame without corrosion (trailers that enter saltwater are inspected in more detail).

• Rollers or Bunk cradles in place, without excessive wear.

• Bow winch working with the strap not frayed.

If you take your trailer for inspection with this list reviewed, your chances of passing on the first attempt drastically increase.

How to pass a trailer's ITV step by step

The process is very similar to that of a car, with two key differences: you must bring the towing vehicle, and the brake test is performed with the assembly hitched.

Step 1: Make an appointment at an ITV station

ITV stations are the same for both cars and trailers. You can choose between a public station managed by the autonomous community or a private authorized station. Appointments are requested online or by phone. Most communities require confirmation that a trailer will be inspected to assign a suitable lane.

Step 2: Attend with the towing vehicle

It is mandatory to present with the car or towing vehicle you will usually use to pull the trailer. Without it, the brake test cannot be performed. This applies to both heavy trailers and light trailers accompanying the car.

Step 3: Present documentation

At the start of the lane, the inspector asks for the ITV card, circulation permit, insurance, and hitch documentation. If everything is correct, they give the go-ahead to enter.

Step 4: Exterior visual inspection

The inspector checks lights, turn signals, reflectors, license plate, chassis, tires, and hitch. Many failures occur here due to burnt-out bulbs or broken reflectors.

Step 5: Brake test

This is performed in a pit or with a brake tester. The car + trailer combination is positioned on rollers that measure the braking force on each trailer wheel. For trailers with an inertia brake, the rollers simulate braking inertia and check that the pads respond symmetrically.

Step 6: Structure inspection

The inspector enters the pit (or raises the assembly on a lift) and checks the chassis, axles, suspension, hitch, and electrical wiring from underneath. This is the phase where structural cracks and significant rust spots appear.

Step 7: Result

There are three possible outcomes:

• Favorable. New sticker stamped. Ready to circulate until the next inspection.

• Unfavorable. Defects detected that must be corrected. You have 2 months to repeat the inspection at the same station, paying a reduced or no fee.

• Negative. Serious defects that prevent circulation. You cannot leave the station towing the assembly; it must be removed by tow truck.

Common errors that cause a trailer to fail the ITV

These are the most common reasons for failure, according to public reports from authorized ITV stations:

• Burnt-out lights or oxidized electrical connector. The most frequent and easiest to avoid error. A replacement bulb costs less than €5.

• Forgotten hitch ball documentation. Without the manufacturer's conformity report and the installation certificate, there's no way to validate the approval.

• Stuck inertia brake. After several months of inactivity, the drawbar actuator rusts and doesn't transmit force to the braking system. This can be resolved with preventative greasing before the appointment.

• Tires with insufficient tread or dimensions different from those on the data sheet. Changing to a tire not approved for that trailer is a guaranteed failure.

• Chassis with advanced corrosion. Especially in boat trailers without hot-dip galvanization. Rust spots on structural welds are a reason for a negative rating.

• Hanging electrical wiring. If there are sections of cable touching the ground or not clipped, it will fail.

• Broken or missing triangular reflectors. Rear ones are mandatory. Without them, it will fail.

What happens if your trailer fails the ITV?

It depends on the rating received. There are three options:

Unfavorable. The trailer has defects that must be corrected, but it is allowed to circulate until the new inspection. You have two months to repeat the test at the same station. If you return within the deadline, the fee is usually reduced or free (varies by station). If two months pass without repeating it, you pay the full fee again.

Negative. Serious defects that prevent circulation. You cannot leave the station towing the trailer. You must request a tow truck or authorized transport. Circulating with a negative rating carries a fine of up to €500 plus vehicle immobilization according to the General Traffic Regulations.

Expired ITV. If you circulate with an expired trailer ITV, the fine ranges from €200 to €500, depending on the time elapsed since expiration. Furthermore, if you have an accident with an expired ITV, the insurance company may claim reimbursement from you for the compensation paid to the third party.

Cost of a trailer ITV in Spain

The price depends on the autonomous community and whether the station is public or private. These are the indicative ranges for 2026:

These prices include VAT. If the ITV is unfavorable, the second inspection within the two-month period is usually free or with a reduced fee of 30-50%, depending on the station. If you exceed the deadline, you pay the full fee again.

To this, you can add the cost of repairing what caused the failure. Lights and bulbs are cheap; an inertia brake disassembled and checked by a workshop can cost €80-150.

Where is a trailer's ITV carried out?

At any authorized ITV station for trailers in your autonomous community. Spanish regulations allow inspections to be carried out at any station in the national network, not just the one corresponding to your domicile. This is useful when you are traveling, have moved to a different province, or live far from the nearest station.

Practical recommendation: call the chosen station beforehand and confirm that it has a line for special vehicles or long trailers. Not all stations have pits prepared for semi-trailers or boat trailers longer than 7 meters. Arriving for your appointment and discovering that the trailer doesn't fit on the line is a wasted trip.

Differences in ITV according to trailer type

Not all trailers are inspected in the same way. Here are the specific points by type.

Light trailers (≤ 750 kg)

They do not undergo their own periodic inspection, but must attend with the towing vehicle. The inspector checks the hitch approval, electrical connection, and general condition. If the car+trailer combination travels frequently, it is advisable to voluntarily inspect it every 2-3 years at a workshop.

Heavy trailers (>750 kg)

Full inspection with brake test. This is the most demanding category. Heavy trailers must have their own ITV card, red license plate, independent insurance, and visible chassis number.

Agricultural trailers

Inspection similar to heavy trailers but with more relaxed criteria on some points (signaling, brakes). Autonomous community regulations apply. They can circulate without brakes up to a specific MMA set by each community.

Caravans and motorhomes

Caravans follow the same schedules as heavy trailers (first ITV at 6 years). Motorhomes follow car schedules (at 4 years). In both cases, the gas installation and proper sealing of hatches and doors are also checked.

Nautical / boat trailers

Inspection with extra focus on the chassis (saltwater corrosion), rollers, waterproof electrical connector, and winch system. Hot-dip galvanized boat trailers pass the ITV much more easily than those simply immersed in galvanization, because structural rust appears years later.

Semi-trailers

They undergo annual ITV from 6 years old (stricter than normal heavy trailers). They are the most used in professional transport. Their brake test requires a towing vehicle approved for that MMA.

Frequently Asked Questions about Trailer ITV

Do I need to take my light trailer for an ITV?

Not periodically. Trailers with an MMA equal to or less than 750 kg do not undergo their own inspection, but must attend with the towing vehicle when it undergoes its ITV and keep the documentation up to date.

How much does it cost to get an ITV for a heavy trailer?

Between €30 and €65 depending on the autonomous community and type of station. For industrial semi-trailers, the cost rises to €70-110.

How often does a heavy trailer need an ITV?

First ITV 2 years from registration. Thereafter: biennial until 6 years, annual until 10, biannual from 10 years.

Can I take the trailer for an ITV without the car?

No. The trailer brake test requires the towing vehicle with which you usually circulate to be hitched.

What happens if I drive with an expired trailer ITV?

A fine of €200 to €500 and potential immobilization of the vehicle. In case of an accident, the insurance company may deny coverage or seek reimbursement from the driver.

Do I need an ITV if my trailer is agricultural?

Yes, if it exceeds 750 kg MMA. The frequency varies by autonomous community. Consult the nearest station before making an appointment.

Where should I put the ITV sticker on a heavy trailer?

On the inside of the towing vehicle's windshield, just like the car's own sticker. The trailer's ITV card is kept with the trailer's documentation, not the car's.

Can I get the ITV before it expires?

Yes. You can get it up to one month before the expiration date without losing days. The new sticker maintains the original date as a reference for the next one.

Remolque.es: your partner to help your trailer pass the ITV without surprises

A well-manufactured trailer passes the ITV first time for many years. A 2 mm hot-dip galvanized steel chassis, EU-approved inertia brake, waterproof electrical installation, and complete documentation delivered with the trailer. This is the factory standard we distribute throughout Spain.

If you need a new European-approved trailer, consult our catalog of boat trailers, machinery trailers, or Tiny House trailers. All come with documentation ready for registration and a 2-year warranty on manufacturing defects.

If you come with a trailer you already own and need specific advice to calmly pass the trailer ITV, Arnaud is your dedicated contact person: he will personally assist you from the first consultation to after-sales. No call centers or unanswered emails.

For any other questions related to driving with a trailer, also consult our guide on the best cars for towing a trailer in Spain and on the maximum permitted load dimensions.