How the currency and time zone settings work
Both are chosen during account creation, in the same short form that most people click through in under a minute. From then on, every cost figure in the account is expressed in that currency, and every reporting day, ad schedule and daily budget reset runs on that clock. The billing country is fixed alongside them.
Neither can be edited later. There is no support request that changes them and no advanced setting hiding the option. The only route to a different currency or time zone is a new account, which means starting again with no cost history, no conversion history and no accumulated signal for automated bidding to learn from. That is why five careless seconds at sign-up can cost a year of comparability.
Why currency and time zone matter
The currency decides how easily your ad cost sits next to your revenue. If the account bills in one currency while the business keeps its books in another, every figure needs converting before anyone can calculate a real cost per lead, and the converted number then moves with the exchange rate as well as with performance. A month can look worse simply because the rate shifted, which is a miserable conversation to have with a client.
The time zone decides when a day begins. Daily budgets reset at account midnight, ad schedules run against account time rather than the visitor’s local time, and “yesterday” in a report means yesterday where the account thinks it lives. Running an evening schedule for Kathmandu customers from an account set to a distant time zone means the hours you selected are not the hours anyone is awake.
Common mistakes with currency and time zone
The common failure is inheriting someone else’s defaults. Accounts created by an agency, a reseller or from a template often carry that party’s country, currency and clock, and the client only discovers it when the first invoice arrives in an unexpected currency. Ask before the account exists, not after.
The second is opening a fresh account purely to correct the setting. Losing conversion history restarts bidding, breaks year-on-year comparison and often costs more than the inconvenience it was meant to solve. The third is comparing spend or day-part performance across two accounts sitting on different clocks and treating the difference as real.
How to get it right
Decide both before anyone clicks create. Choose the currency your business reports in, unless the card or bank account that will pay is denominated elsewhere and your accountant would rather avoid a second conversion. Choose the time zone your team plans and reports in, then record both in the account name so nobody guesses later.
If an existing account is already wrong, the usual answer is to live with it and document a fixed conversion policy rather than rebuild. Reserve a fresh start for cases where the mismatch genuinely distorts decisions, and treat it as a migration: new conversion actions, rebuilt linked accounts, bidding back in its learning period. Getting this right at account setup is far cheaper than repairing it.