did you transfer some funds from the old to the new account ?

if so, you could create a GL 1011 - new bank

  in sage, transfer funds (to match what really happened) - so both bank stmt reconciliations will balance

  in sage, under setup, change all bank linked accounts from 1010 to 1011

Both accounts have balances in them for July and August but all the entries in Sage/Simply have been entered using acct #1010. If I create a new account now or change the linked accts, will that effect all the july & august entries (chqs & deposits)?

Both accounts have balances in them for July and August but all the entries in Sage/Simply have been entered using acct #1010. If I create a new account now or change the linked accts, will that effect all the july & august entries (chqs & deposits)?

You should always have only one Sage 50 account nbr for each bank acct. I would suggest you create a new G/L account nbr for the new bank account and then go thru each #1010 bank entry that is for the new bank acct and do an autoadjust to show new G/L acct nbr. It won't matter at this point which linked account is being used as bank since you will still be able to select the "From" bank account to change from 1010 to the new bank act nbr. Once you have autoadjusted  all the entries that affects the new bank account then you will be able to reconcile each G/L bank acct nbr separately. Then I would suggest to change the linked account to the new bank that you are now using.

You should never use the same G/L Acct nbr for more than one bank account. The name should reflect the bank name as well such as 1010 TD Bank, 1011 RB Bank, 1012 RB Savings, etc.