I think I'm getting the hang of this but can someone confirm that I've got this one right.

My client was in receipt of Tax Credits on a joint claim with her husband. Her husband died on 6 November. She needs to make a new claim as a single claimant for the purpose of which I understand she would need to provide information about only her income during 03-04 and that changes in just her income during the current year would affect her entitlement.

Yes?

I believe so, for the new claim.

She will also have the old joint claim, so she will in effect have two claims for this year.

The periods she is claiming for will be different. But income is still for the whole year? If so, her income for the first part of the year will be counted twice, once for the old claim and once for the new claim. Does this matter? I am not sure.

Also, be careful they don't automatically backdate her new claim to a period prior to her husband's death. That could cause a lot of unpleasantness come next April.