There are two common ways to track cash in hledger. One is to have a separate account for cash and keep track of each time you spend or acquire cash. You reconcile your cash account against the amount of cash in your wallet, pocketbook, the plastic bag under your bed, the coffee can buried in the back yard, or wherever.
The second method is to just treat any acquisition of cash as immediately spent. For example, you could use a category such as EXPENSES:CASH. Every time that you acquire some cash, you immediately record the same amount as spent under EXPENSES:CASH. The advantage of this method is that it is faster, in the sense that you don’t have to save receipts from every time that you have a cash expense and then enter them in your plain text accounting file. The disadvantage is that you don’t know where your cash goes.
For me, a key point in deciding which method to use is how much cash I spend. And what does “how much cash” mean? I think that a good place to start is the amount spent relative to your total expenses. For example, I just checked our expenditures for 2025, and our cash expenses were a bit less than one half of one percent. For me, that’s a relatively small amount, so I don’t mind not knowing exactly where the money was spent. I know that it was spent in miscellaneous cash expenses, but not precisely where.
On the other hand, if cash expenses were 20% of my total expenditures, I would definitely want to keep track of each cash transaction so that I would have a clear picture of what was happening with that 20%.
Finally, I think that there are some people who simply want to know exactly where they are spending their money, and they will feel good tracking every cash expenditure. In my case, I am satisfied tracking more than 99.5% exactly and the remaining amount just as “something spent using cash.”