If you pay it off it will still show on the credit agency reports...Experian & Equifax being the main two for several years. If you have a credit card and clear this monthly or just retain a nil balance this will be a positive on your credit report.
Also things like mobile phone accounts car insurance (if paid monthly) can also show on your credit report and as long as paid each month help to improve your credit rating too. Personally I'd pay it off if you are able to.