Try: =INT((A1-DATE(YEAR(A1)-(TEXT(A1,"mdd")+0<406),3,30))/7)

Where A1 houses the date you want to return the weeknum for.

Regards
Jon von der Heyden
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Email: subst1tut3 numb3rs for l3tt3rs...


"Trevor Aiston" wrote:

Is there a switch I can use with weeknum function that will calculate week
numbers based on UK tax year rather than calender year?

TIA

Trevor