Mere Bookkeeping is designed to track a single year within a workbook. There are two methods for starting a new year:
Get the latest templates to setup a new year from scratch. Setup your new year by following the instructions on the Welcome sheet and User Guide (though, you can copy/paste a lot of your settings, funds, accounts, contacts to speed things up).
Learn how to migrate from an old version to a new version.
Create a copy of your current workbook (if you don't want the latest version of Mere Bookkeeping, or if you're already using the latest version).
Click File > Make a Copy in the Google Sheets file menu.
Rename your new workbook with the appropriate year in the file name. Click “Make a Copy”.
Your new, copied workbook will open in a new window.
Go to the Journal sheet and highlight all rows with transactions (not your header rows) and clear the transaction contents using the Delete key (remember, this is a copy, so you still have last year's transactions in the original file).
Update your fiscal year start date in the Settings sheet.
Change back to the default "Current Date" setting in Date Controls to begin the new year.
In your prior-year workbook, ensure Date Controls are set to include the entire completed fiscal year. Then, use the ending balances from its Fund Balances report as the beginning balances in your new workbook’s Funds sheet.
If you have outstanding (pending) transactions in your old workbook, you'll need to account for these in your new workbook until they clear. In your Reconciliation sheet (below your bank balances), enter a temporary line for outstanding year-end revenue (negative amount) and another for outstanding year-end expenses (positive amount) and adjust/remove these values as your prior-year tranactions are posted.
Make any edits to your account groups, accounts, and budgets for the upcoming year.
Clear complete statuses in your Checklist worksheet, while keeping the names of the tasks.
Review recurring transactions and amounts for the new year.
Clear any contacts you don’t expect to need anymore, then re-sort by name.
You'll also need to share any reports in your new workbook that you previously shared with others (generating new share URL's).
And with that, you’re ready to start entering transactions for the next year!
Whichever method you choose, you'll still end up with a new workbook for your new year. This means your workbook from the prior year will remain as an archive.