You can set up recurring (or repeating) expenses here: These will show up as future expenses on your Cash Flow and also show up under Bills Due on your Dashboard's Spending Stats.

Please note: If you have your data auto-importing from your financial accounts, this may result in duplicates. Be sure to delete one of the paid expenses to avoid inaccurate reporting. You can also create these in a manual bank account that you have to NOT report to your Profit & Loss, then once a month go through and mark them as paid as soon as they clear your bank account.