Guidance for (Acting) Returning Officers administering a UK Parliamentary election in Great Britain

Ballot paper design

Ballot paper numbers

Ballot paper numbers should run consecutively, but do not have to start at ‘1’. Ballot paper numbers should be unique, and should not be reused, for example the polling station, postal vote and tendered ballot papers should all be numbered differently. 

Form of the reverse of the ballot paper

The form of the reverse of the ballot paper is prescribed and you must ensure that the required information is included on the ballot paper reverse in the specified format.1 There is no provision to put any hatching or other marks on the back of the ballot paper. 

Unique identifying mark (UIM)

The unique identifying mark can be made up of letters and numbers and could be a repeat of the ballot paper number with the addition of a prefix or a suffix. The unique identifying mark can instead be, but does not have to be, a barcode. It is important to remember that the unique identifying mark is not the same as the official mark. 

The unique identifying mark:2  

  • should be unique for each ballot paper
  • can be re-used at the next poll
  • must be printed on the back of the ballot paper

The official mark

The official mark is a security mark that must be added to the ballot paper.
The official mark:3  

  • can be the same for all ballot papers at an election or different official marks can be used for different purposes at the same election, for example one for postal votes and another for polling station ballot papers
  • cannot be re-used for seven years at a UK Parliamentary election to the same constituency

The mark should be distinctive. It could be a printed emblem or mark or a special printing device such as a watermark. It could also be a perforation added at the time of issue of the ballot paper if stamping instruments are used to create a perforating official mark.  

The mark should be capable of being seen on the front of the ballot paper without having to turn the ballot paper over.4  

Ballot paper colour

The colour of ballot papers is not prescribed and is for you to determine. 

Tendered ballot papers are required by law to be a different colour from the ordinary ballot papers.5  

In deciding on the ballot paper colour you should take into account accessibility issues relating to colour and contrast. See our 'Making your mark’ good practice design guidance for more information on choosing ballot paper colours. 

Cross-boundary constituencies and combinations

You should decide at an early stage in the planning process and in consultation with the local government RO(s) in your constituency, what colour the UK Parliamentary ballot paper will be in your constituency. You should liaise with the other RO(s) in your constituency to ensure that in the event of a combined election the ballot paper colours are different for each election.

Last updated: 19 December 2023