Every imported Mercedes resolves to an eight-digit statistical code — Revenue's link between your exact car and the OMSP it taxes, returned when you run the VIN through the ROS VRT enquiry. Get the generation wrong and even a diesel like a C220d, which runs the CO₂ table plus the NOx levy, lands on someone else's OMSP.
C-Class: read the generation before the trim
The C-Class is the model where Irish importers most often reach for the trim and skip the chassis, and that is the wrong order. A C200, a C220 CDI and a C250 are each coded apart, and the saloon, estate and coupé bodies split them again — but all of that sits underneath a bigger fork: which generation you are actually looking at. The outgoing W204 (roughly 2007–2014) and the W205 that replaced it are different cars in Revenue's database, so a W204 C220 CDI is not the same row as a W205 C220 d even though the numbers look almost identical.
Getting the generation right is therefore the first fork, not a detail you settle at the end. Fix the chassis from the registration year and the VIN, then narrow by engine and body — the same discipline that keeps importers of a BMW 5 Series or an Audi A4 from matching a facelift to the previous shape. Do it the other way round and a cheap-looking C-Class row is usually the wrong generation entirely.
E-Class: three generations under one badge
The E-Class turns the same problem up a notch, because its most common diesel has outlived three separate chassis. A single E220 search on ROS can span the W211, the W212 and the current W213, and each generation is coded independently — three distinct rows, each with its own OMSP, all wearing the same three digits on the bootlid. On top of that, every one of those generations splits between saloon and estate, so a plausible-looking match can still be the wrong body.
The practical consequence is that "E220" alone tells you almost nothing. A 2009 CDI, a 2015 BlueTEC and a 2020 d are three different cars for VRT, and only one of them is yours — so you narrow the lookup by year and body before you trust any figure it returns.
CLK 220 CDI and the legacy lists
Older Mercedes bring a different trap: the model may have left the current lists altogether. The CLK was discontinued years ago, and a CLK 220 CDI is exactly the kind of car that no longer appears in the main current-model tables. When the ROS enquiry returns nothing for the trim or body you have, the next place to look is Revenue's legacy code lists, where discontinued models are kept so they can still be registered.
Body style matters here too. A CLK sold as a coupé and one sold as a cabriolet of the same year and engine are separate entries, and both may live only in those legacy lists rather than alongside current cars. If a third-party lookup shows the CLK as simply "not found", that is rarely the end of the road — it usually means you are searching the wrong list, not that the code does not exist.
Mercedes code splits at a glance
The splits that most often trip up Mercedes importers, with the generation or list check to make before your NCTS appointment:
| Model | Variants with separate codes | Import note |
|---|---|---|
| C-Class | W204 vs W205, C200 / C220 CDI / C250, saloon / estate / coupé | Fix the generation first — a W204 C220 CDI is a different row from a W205 C220 d |
| E220 | W211 / W212 / W213, saloon vs estate | One badge spans three chassis — narrow by year and body before trusting an OMSP |
| CLK 220 CDI | Coupé vs cabriolet, discontinued generation | Often only in the legacy code lists — a blank current-list result is not "no code" |
Mercedes VRT questions
Does a W204 C-Class share a code with a W205?
No. The W204 and W205 are different generations of the C-Class and sit on separate statistical codes with their own OMSPs, even when the badge reads the same. Confirm the chassis generation from the year and VIN first, because a C220 CDI in a W204 is a distinct entry from a C220 d in a W205.
Why does one "E220" search return three different cars?
Because the E220 badge spans three chassis — the W211, the W212 and the W213 — and each generation is coded independently, then splits again between saloon and estate. A single "E220" lookup can surface several plausible rows where only one matches your car, so narrow it by registration year and body before you trust any OMSP.
Why does my CLK 220 CDI only appear in the legacy code lists?
The CLK was discontinued years ago, so some versions no longer sit in the main current-model lists and are only found in Revenue's legacy code lists. If the ROS enquiry returns nothing for your trim or body, that is usually where to look next — and where a coupé and a cabriolet of the same year still separate into their own codes.