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HMRC internal manual

Self Assessment Manual

Returns: individuals returns: taxpayer carries out more than one trade (Action Guide)

Where the return includes more than one trading source, (there are multiple Self Employment supplementary pages attached to the return), follow steps 1 - 2 below. For details of how to access the SA function, select ‘Index Of Functions’ on the left of the screen.

1. Use function MAINTAIN SOURCES and make a note of the source reference for each source. You may want to do so on the relevant pages of the return if so use pencil   
2. Enter the source reference during capture