How do I close a period for a reconciled account?
To close a period, you must do a reconciliation and record it. This is done by selecting the Recon button from the Toolbar. It is not essential that all accounts are reconciled at the same time. They can get out of step without effecting anything other than reports based on all accounts. See Reconcile.
How do I open a new period?
Opening a new period is exactly the same as closing the current period (see above). You must reconcile your old period with your statement and then record it. This will then automatically open the next period.
Naturally if March is the current period and you reconcile it, April will automatically be opened and then become the new current period for that particular account only. You cannot skip a period. They must be opened in sequence.
See Reconcile
How do I open a new financial year?
At the close of your business period, usually the financial year, simply reconcile for the last period. This opens the first period of the new business period.
In the first couple of periods in the new business period you will probably have withdrawals and deposits come through your account that you would like to include in the old business period. If this is the case you may enter them in the reconciled periods of the old business period, but they cannot be cleared in those periods. They can only be cleared in the new business period.