Google doesn’t monitor your store. If you close the store, *you* need to turn off AdWords.

There is one case where adverts will stop to a closed store, or a malfunctioning store – if the pages return a “404″ (Page Not Found) status. Eventually (which may be a few minutes or a few days), Google’s advertising bot, Adsbot, will notice and start disabling adverts. AFAICS, the reason for Google to do so, is to ensure that search users get a good experience, not to help advertisers.

If you’ve closed your AdWords account, then you shouldn’t be being charged for any more adverts. However, if your account is billed in arrears, then you could face a future bill for clicks delivered up until the account was closed. That might take a few weeks to resolve, especially since Google tries to lump multiple click payments into larger credit card transactions. If you had clicks after the last credit card charge, then there should still be one or perhaps two more transactions to the card to catch up with activity up to the point at which you stopped advertising.

If you’ve closed your AdWords account and it is still accruing clicks and charges, that’s a completely different matter. Google should be quite helpful about refunding clicks if you’ve clearly indicated that you are trying to shut the AdWords account down.

Cheers, JeremyC.