Look at WORKDAY, it is not a native excel function but it comes
with excel/office and it can be either installed when you first install
office/excel or it can be added later

=WORKDAY(A1,20,Holidays)

where A1 is the start date, 20 is the workdays and Holidays is range with
public holidays

=WORKDAY(A1,20,H1:H11)

where you would put each holiday date in H1:H11

if you get a name error, do toolsadd-ins and select ATP (Analaysis
ToolPak), follow the directions and keep the office/excel cd handy


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Regards,

Peo Sjoblom

"Pete" wrote in message
...
Ideally I would like a formula that will add 20 working days (British
calendar) to a date in another cell. I don't know if this is possible so
as
an alternative, what would the formula be for 20 weekdays?

Many thanks,
Pete