I found this which will replace the square brackets and the numbers inside with bold, but how can I just have the numbers bold?

Press Ctrl+H to activate the Replace dialog
Click More >>


Tick the check box Use wildcards
In the Find what box, enter \(*\)
Click in the Replace box
Leave it blank, but next click Format > Font... at the bottom of the dialog
Click on Bold, then click OK
Click Replace All

That Find/Replace works with parentheses, not square brackets! Assuming it's parentheses you're working with, simply use a second wildcard Find/Replace where:
Find = [\(\)] - with Format|Font|Bold
Replace = ^& - with Format|Font|Not Bold

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]

Hi Paul & thanks for the reply,

They actually are square brackets and I had changed the instructions above to square brackets, but forgot to post with square brackets.

I guess modifying your suggestion with square brackets is also not the right answer.

I tried \[*\] but it bolds all numbers and the square brackets

As per my previous reply, you need two wildcard F/R operations:
Find = \[*\]
Replace = ^& - with Format|Font|Bold
Find = [\[\]] - with Format|Font|Bold
Replace = ^& - with Format|Font|Not Bold

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]

Sorry about that Paul...in my haste I misread your first post. Works well thanks.