I highly recommend reading beancount’s documentation on this, as what I have in this document does not draw from the same well of experience that beancount does:

• Beancount - The Double-Entry Counting Method # Types of Accounts

This document is highly derivative of beancount’s documentation, and is only included for completeness.

There are 4 conventional “root accounts”:

• Assets: Accounts you can draw from to trade with other people. Like a bank account containing money. Or some stocks you own.
• Liabilities: Accounts that you have to pay off. Credit cards, bar tabs, unpaid taxes, that sort of stuff.
• Income: A source of money.
• Expenses: A sink of money.

The balance of conventional “root accounts” have different “preferred” ways of being inspected:

• For Assets and Liabilities what matters is how much you have at a given point in time.
• For Income and Expenses the change over a given period of time matters more.

The conventional “root accounts” have a sign associated with them:

• Assets and Expenses are positive (+).
• Income and Liabilities are negative (-).

We can put this on a two axis chart:

Opening Date for Expenses

Expenses will often be abstract categories, so theres not an obvious opening date. I use my birthdate, you could use the first time you log an expense in that category. Whatever floats your boat.