Emissions standard
Euro 6
Checked on 20 June 2007.EUR-Lex, Regulation (EC) No 715/2007, Annex I tables 1 and 2: Euro 5 and Euro 6 emission limits (as of 20 June 2007)
Euro 6 clean air zone status
Compliant
A petrol car at Euro 6 meets the Euro 4 pass mark every UK zone applies to petrol.
Compliant
A diesel at Euro 6 meets the Euro 6 pass mark every UK zone applies to diesel.
What is Euro 6?
Euro 6 is a stage of European vehicle pollutant limits. The diesel pass mark for every UK clean air zone. Diesel nitrogen oxides fell from 180 to 80 mg/km, which is the change the whole zone system is built on, and a particle number limit reached direct injection petrol for the first time. That petrol particle limit only became binding for new registrations on 1 September 2018, three years after the main stage.
Euro 6 limits, in g/km
| Pollutant | Petrol | Diesel | Change from Euro 5 |
|---|---|---|---|
| Carbon monoxide (CO) | 1 | 0.5 | 0 per cent lower on diesel |
| Hydrocarbons (HC) | 0.1 | No limit set | |
| Hydrocarbons and NOx combined | No limit set | 0.17 | 26 per cent lower on diesel |
| Nitrogen oxides (NOx) | 0.06 | 0.08 | 56 per cent lower on diesel |
| Particulate matter (PM) | 0.0045 | 0.0045 | 10 per cent lower on diesel |
This stage also sets a particle number limit of 6e+11 particles per kilometre, which counts the particles rather than weighing them. A filter can pass on mass and still fail on number, which is why the second limit was added.
Which cars had to meet Euro 6
Euro 6 applied to new passenger car type approvals from 1 September 2014 and to new registrations from 1 September 2015. From that September 2015 date a new car in this timetable could not be registered below Euro 6. Regulation (EC) No 715/2007 set the limit table. Later Commission regulation added the substage dates.
This is the diesel pass mark for every UK clean air zone that charges cars. A diesel that holds Euro 6 meets the test. A petrol car already met its test at Euro 4, so Euro 6 petrol is a pass as well. For the first time in this series, both fuels clear the zone on the stage number.
2015 is a diesel straddle year. A diesel first registered in March 2015 is on the Euro 5 side of the compulsory line unless it was certified early. A diesel first registered on or after 1 September 2015 had to meet Euro 6. The month is the whole difference.
Diesel nitrogen oxides fall to 0.08 g/km
Diesel nitrogen oxides fall from 0.18 g/km at Euro 5 to 0.08 g/km at Euro 6. Converted from that g/km table those figures are 180 mg/km and 80 mg/km, which is the change the Euro 6 summary says the whole zone system is built on. Diesel combined hydrocarbons and nitrogen oxides fall from 0.23 g/km to 0.17 g/km. Diesel carbon monoxide stays at 0.5 g/km. Diesel particulates are 0.0045 g/km, with the same 6e11 particle number limit.
Petrol carbon monoxide stays at 1.0 g/km, hydrocarbons at 0.1 g/km and nitrogen oxides at 0.06 g/km. Petrol particulates are 0.0045 g/km for direct injection. Petrol also gains a particle number limit of 6e11 per kilometre. That petrol particle number limit only became binding for new registrations on 1 September 2018, three years after the main stage.
Letters after Euro 6, such as 6b, 6c, 6d and 6d-TEMP, are substages of the same stage number. No UK zone in this dataset sets its pass mark finer than Euro 6. A zone that has the car as Euro 6 will not then fail it for missing a letter.
- Diesel nitrogen oxides: 0.08 g/km, down from 0.18 g/km at Euro 5.
- Petrol particle number: 6e11 per kilometre, binding for new registrations from 1 September 2018.
- Clean air zones read Euro 6, not RDE2 and not a 6d letter.
RDE2 is an extra diesel test, not a Euro number
RDE2 is the second step of the Real Driving Emissions test. It measures nitrogen oxide output on the road rather than only on a laboratory cycle. It is not Euro 7, and it is not a replacement for Euro 6. A car can be Euro 6 and not certified to RDE2.
What RDE2 changes for a UK driver is first year vehicle tax and company car tax, not the clean air zone. A diesel first registered after 1 April 2018 that is not certified to RDE2 pays the first year rate of the band above its own. HMRC treats RDE2 and Euro 6d as the same thing for company car tax. Neither of those tax rules is a ULEZ rule.
Nothing on a V5C says RDE2 in the way V.9 says Euro 6. The certificate of conformity is the document that shows Real Driving Emissions certification. A zone operator who has the car as Euro 6 will not then ask for RDE2 before letting it in.
Euro 6 diesel is the zone pass
A Euro 6 diesel meets Euro 6. A Euro 6 petrol meets Euro 4. Both fuels drive in free on emissions grounds in the London ULEZ, the English clean air zones and the Scottish low emission zones. Scottish zones still ban a non compliant vehicle outright, but a Euro 6 car of either fuel is compliant.
Battery electric cars are outside this table altogether: they have no tailpipe stage to hold. A hybrid is judged on its petrol or diesel engine, so a Euro 6 diesel hybrid passes as a diesel Euro 6 car, and an older diesel hybrid at Euro 5 still pays.
Example
A diesel first registered on 2 September 2015
- Fuel
- Diesel
- First registered
- 2 September 2015
- Euro 6 type approval from
- 1 September 2014
- Euro 6 new registrations from
- 1 September 2015
- Diesel NOx at Euro 6
- 0.08 g/km
- 2 September 2015 is on or after 1 September 2015, so a new diesel could not be registered below Euro 6.
- Diesel nitrogen oxides at this stage are 0.08 g/km, against 0.18 g/km at Euro 5.
- Euro 6 is the diesel pass mark of Euro 6, so the car meets every UK car zone on diesel.
- RDE2 is not required for that zone result. It is a separate on road test used in first year tax after 1 April 2018.
A diesel first registered new on 2 September 2015 meets the diesel zone test by law. Confirm V.9. Do not confuse that pass with RDE2 certification, which the V5C does not show.
How to prove Euro 6 to a zone
V.9 that names Euro 6 is the pass, on either fuel. If a Euro 6 diesel is still being charged, the operator's list is wrong or the fuel has been stored as something else. The certificate of conformity is the correction, including the substage letter if you need it for tax rather than for the zone.
For a diesel registered in 2015, the date on either side of 1 September is the usual fight. A car registered on 20 August 2015 infers Euro 5 as the compulsory floor. Early Euro 6 type approval from 1 September 2014 is the only way that August car passes, and it has to be on the certificate.
- Read V.9. Euro 6 on petrol or diesel is a zone pass.
- If V.9 is blank and the car was first registered new on or after 1 September 2015, infer Euro 6 as the floor.
- If the diesel was registered earlier in 2015, get the certificate of conformity before you tell a zone it is Euro 6.
- Use the same certificate to show RDE2 or Euro 6d if the question is first year tax or company car tax, not the zone.
- Send the certificate to the operating authority if a Euro 6 car is generating charges.
2015 diesels, 2018 petrol particle number and imports
A diesel imported in 2016 with a 2014 continental first registration can be Euro 5 or Euro 6. The UK plate year of 2016 infers Euro 6 only if you treat the UK date as a new car date, which it may not be. The certificate of conformity is the safe document. Guessing from the UK year on a used import is how a Euro 5 diesel gets a free pass it has not earned, or a Euro 6 diesel gets charged.
Petrol particle number becoming binding on 1 September 2018 does not create a new zone test. A petrol car registered in 2016 is already Euro 6 for the zone. The 2018 date is about the particle number limit on new petrol registrations, not about whether the car may enter Birmingham or Glasgow.
- Letters after Euro 6 are substages. UK car zones do not use them as a pass mark.
- A Q plate still has no age. Euro 6 cannot be read off a Q mark.
- Van Euro 6 in a zone is the same pass mark, not the same introduction date as 1 September 2015 unless a van source says so.
Common questions
- When did Euro 6 become compulsory for new cars?
- New type approvals from 1 September 2014, and new passenger car registrations from 1 September 2015. A new diesel registered from that September 2015 date had to meet Euro 6.
- Does a Euro 6 diesel pass every UK clean air zone?
- Yes, on emissions grounds, in every scheme in this dataset that charges cars. Euro 6 is the diesel pass mark in London, the English clean air zones and the Scottish low emission zones.
- Is RDE2 the same as Euro 6?
- No. RDE2 is an extra on road nitrogen oxide test for diesels. Euro 6 is the stage number. A car can be Euro 6 without RDE2. Zones use the stage. First year tax after 1 April 2018 uses RDE2. HMRC treats RDE2 and Euro 6d as the same thing for company car tax.
- Is a 2015 diesel ULEZ compliant?
- It depends on the month. From 1 September 2015 a new diesel had to meet Euro 6. Earlier in 2015 it may be Euro 5. V.9 or the certificate of conformity is the proof. The year 2015 is not.
- What is the Euro 6 diesel nitrogen oxide limit?
- 0.08 g/km in the type approval table. Euro 5 was 0.18 g/km. Converted from that g/km table those figures are 80 mg/km and 180 mg/km. The zone reads the stage, not a roadside milligram test.
- When did petrol particle number become binding?
- For new registrations, on 1 September 2018, three years after the main Euro 6 stage. The limit is 6e11 particles per kilometre. It does not change the petrol zone pass, which was already won at Euro 4.
- Does Euro 6d pass a zone if Euro 6 does?
- Yes. 6d is a substage of Euro 6. UK car zones use the whole number. Euro 6d matters more for company car tax, where HMRC treats it as RDE2.
- If V.9 says Euro 6, do I still need the certificate of conformity?
- Not for a correctly recorded zone pass. You need the certificate if the operator has a different stage on file, if V.9 is blank, or if you need RDE2 or a 6d letter for tax.
Sources
- EUR-Lex, Regulation (EC) No 715/2007, Annex I tables 1 and 2: Euro 5 and Euro 6 emission limits (as of 20 June 2007)
- EUR-Lex, Commission Regulation (EU) No 459/2012: revised particulate protocol and the Euro 5b, 6b and 6c implementation dates (as of 29 May 2012)
- EUR-Lex, Council Directive 1999/37/EC, Annex I: harmonised codes on vehicle registration documents, V.9 environmental category of EC type-approval (as of 29 April 1999)