How often do lenders usually update credit files?

Plutonomics

I'm just curious, does anyone know whether creditors usually update account balances monthly or can it sometimes be longer? The reason I ask is that I completed a balance transfer in early August and although my new card balance is showing, the balance is still showing on my old cards. I can see several accounts have a "last updated" date in the past few days, but the three cards I transferred from to the new card all show as last updated on the 3rd or the 7th August, I'm not too worried at the moment as I don't intend applying for any credit, though of course would like this gone as it's greatly inflating my total debt figure on my credit report.

aNom

I've found initial updates can be up to 8 weeks depending on when the account was setup but subsequent updates are normally monthly.

Ben8282

Most updates are monthly but Lloyds and TSB seem to update whenever they feel like it - current accounts and credit cards.
Another problem I have is that the current month does not refer to the same month with different lenders.
For example, I have one old card which does not show the enhanced reporting, just a balance and status code (not even a code to say that I paid in full), which updates promptly and the current balance showing is the balance of the statement issued 1st September.
By contrast, current month info for Lloyds and TSB cards (I have both) is 10th June statement with the balance at the top being the balance after payment due date of June statements. Last update on both accounts was 8th August. September statements have already been issued on both accounts.
My credit files can therefore NEVER show a correct balance or utilisation % in respect of any particular month.