The emission key number: what field 14.1 says about your sticker

Independent, non-governmental site: not an authority’s service, no sticker sales.

The Euro norm and fuel sit next to the key number in the papers: the check gives a first answer from them, and the issuing office reads the number itself.

Vehicle
Work it out from

Your vehicle gets

Green sticker

Emission group 4

Into the 35 active zonesyes
Legal basisAnnex 2(1), Federal Environment Ministry simplified table
Fee at the issuing office€5 – €10

Green is not enough everywhere: Stuttgart bans diesels up to Euro 4 (up to Euro 5 in the small zone), Munich diesels up to Euro 4.

35th BImSchV, Annex 2: assignment to emission groups · BMUV table

How the check works and its sources

For a vehicle registered in Germany the emission group is not set by the year of manufacture but by the emission key number. Section 5 of the 35th BImSchV says so: the group is proven by the key number entered in registration certificate part I, the old Fahrzeugschein or the Fahrzeugbrief. In today’s registration certificate it sits in field 14.1, with the Euro norm written out in field 14. The Federal Transport Ministry publishes in the Verkehrsblatt which number belongs to which group. We found no complete official table at federal level that anyone can read freely, so our check asks for fuel and Euro norm, which appear in the same papers and lead to the same result for almost every vehicle. In case of doubt, such as special cases or retrofits, only the number the issuing office reads from your papers counts. For heavy goods vehicles in the toll system, the proofs under the truck toll ordinance are also accepted.

Checked by Radif Partners · Editorial policy · Method and sources

Why the number and not the year

Two cars from the same year can be in different groups: one was approved to a newer norm, another has a retrofitted filter, a third meets an older norm. The year says nothing reliable about that. The key number, by contrast, stands for the specific type approval. That is why section 5 of the 35th BImSchV requires it as proof, and why the date-based check on this site is only meant for foreign vehicles.

How to use the check above

  1. Read field 14: it shows the norm, such as “EURO 4” or “EURO 5”. Pick that in the check.
  2. Read the fuel in field P.3: petrol, diesel, gas or electric.
  3. If the papers mention a particle reduction system on a diesel up to Euro 3, set the switch to “Yes”.
  4. Compare the result with the sticker the issuing office derives from the number; if they differ, the issuing office is right.

The limits of this page

We deliberately reproduce no list of key numbers: the official assignment appears in the Verkehrsblatt, which we could not consult in full, and we will not pass off an unchecked third-party list as official. This limit is also stated in the method. The rules for the sticker colour are on the which sticker? page, and retrofits are covered on the particle filter retrofit page.

Frequently asked questions

Where exactly is the key number on the registration certificate?

On registration certificate part I, the small vehicle document, in field 14.1. Field 14 above it gives the name of the emission standard, such as “EURO 6” or a directive with a year. In old vehicle documents from before 2005 the entry was called “Schlüsselnummer zu 1” and sat among the vehicle details. The sticker issuing office needs exactly this figure.

What do key numbers ending 01, 02 and 77 mean for petrol cars?

The City of Stuttgart lists them as a special case: older petrol cars with a US catalytic converter whose key number ends in 01, 02 or 77 also get the green sticker. Such cars formally have no Euro norm but meet equivalent requirements. If you drive one, have the assignment confirmed directly at the registration office or a testing body.

My key number does not reflect the retrofitted filter. What now?

After retrofitting a particle reduction system the new key number must be entered in the papers; the registration office does this using the garage’s fitting certificate. Only then will an issuing office hand out the higher sticker. With the old number the vehicle stays in its old group, even if the filter already works technically.

Related pages and checks

Which sticker?

Enter fuel and Euro norm: the sticker colour under the 35th BImSchV.

Getting the sticker

Registration office, TÜV, DEKRA or an approved workshop: who issues it, what it costs, what to bring.

Particle filter

When a retrofitted filter lifts an old diesel from yellow to green, and when it does not.

Foreign vehicles

With no proof of the norm, the first registration date decides: the section 6 presumption.

Green sticker

Who gets group 4, why yellow and red no longer work anywhere, where green is not enough.

Stuttgart

The whole city is a zone, plus diesel bans up to Euro 4 and up to Euro 5 in the small zone.

Sources

Written by

Publisher of an independent reference on German low-emission zones that traces every zone back to the Federal Environment Agency register and the clean-air plan behind it

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