Select B3. Format>Conditional Format. Choose Formula is. Enter this
condition =DAY(B3+1)=1
Select Borders and choose your favorit.

Copy B3. Select all the other cells. edit>Paste Special, check Format

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Kind regards,

Niek Otten

Microsoft MVP - Excel

"Bill" <Bill@discussions.microsoft.com> wrote in message
news:406B6111-31F6-4133-A7CD-C87A1A0EC9CC@microsoft.com...
>I have a spreadsheet that list three months of dates. Row 3 list the day
>for
> each month. Example
>
> B3 = 1
> C3 = 2
> D3 = 3
> E3 = 4......And so on...
> eventually CO3 = 31
>
> I need to accomplish two tasks using VBA for Excel.
>
> 1. I need to apply a verticle line to the right side of the column when
> it
> equals the last day of the month. As an example... If the starting month
> is
> Feb 05, then a thick border would be applied to the right side of colum AC
> because AC3 contains the last day of the month (28) for Feb. Columns BH
> and
> CL would also have a thick border applied to the right side since BH3 and
> CL3
> contain the last working day for those months.