just to give you a tip... if your number is going to contain those dashes, I would definitely incorporate that in your pattern and not just pick the first 5 digits.  i mean, i don't know your source but it it is a body of text then i would definitely be much more specific.

happy PMing.  :-)

I'm using the pattern (\w+) would you recommend a different solution?

I would probably recommend (\d+) instead unless you want to return more than just numbers

\d represents a decimal digit (0-9)

\w represents a word character (letters, numbers, and connecting punctuation) See Word Character: \w