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Last reviewed: 6 July 2026
V55/5 form · Box 40
CO — Carbon Monoxide (g/km or g/kWh)
What goes in box 40
Box 40 of the DVLA V55/5 form is for co — carbon monoxide (g/km or g/kwh).
The carbon monoxide figure from the Certificate of Conformity emissions section. On EU registration certificates it's field V.1. Leave blank if you don't have this information.
What to enter
| Field | Type | Required? |
|---|---|---|
CO (g/km or g/kWh) The carbon monoxide figure from the Certificate of Conformity emissions section. On EU registration certificates it's field V.1. Leave blank if you don't have this information. | number | Optional |
Source
This page is generated from the same field definitions our V55/5 tool validates against, mapped to the official DVLA guidance.
V355/5 official guidance (GOV.UK)v55-5.com is an independent service and is not affiliated with the DVLA.
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