Hi Ian,
Without knowing how the date is selected on your form, it's difficult to answer your question. Does the user type the date into a textbox? Or select it from a drop-down menu?
I usually have three separate drop-downs on my userforms for date selection. Combobox1 contains year, Combobox2 contains month, and Combobox3 contains day. Then I have a commandbutton at the bottom of the form. To enter my data onto a cell in the worksheet, I do this:
Sub CommandButton4_Click
Sheet1.Range("A1").Value = UserForm1.Combobox2.Value & "/" & UserForm1.Combobox3.Value & "/" & UserForm1.Combobox1.Value
End Sub
Let us know if you need more help.