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FAFO: A budgeting system for responsible adults

tl;dr

This is a lightweight system for budgeting where you track four categories of expenses: Fixed, individual Allowances, Flex, and Other. At the end of each month, you retroactively reconcile your budget and put spillover/spillunder into Other, which carries over to the next month, and you adjust your spending habits accordingly.

Why I do it this way

In an ideal world, we’d have a list of all expenses we would make during a month arranged into some kind of Maslowian hierarchy, and we’d just draw a line near our targeted spending amount and pay for everything under it. But since we don’t actually know the amounts for all of the expenses beforehand, we need to rely on estimates. This helps us to develop as accurate a prediction as possible about where the line needs to be drawn.

I find most budgeting systems (eg envelope budgeting) to be oppressive and high-overhead. FAFO gives you flexibility and lightweight tracking at the cost of increased responsibility. If envelope budgeting is like flying coach in a straitjacket (and it is), FAFO is like sitting in the cockpit with a compass and a map. You get more freedom, including the freedom to nosedive into the ground.

Would it work for you?

All of these should be true:

Tools

You can use whatever you want, but the terminology here is tailored to what I’ve found to be the best combination of cheap (~$1/mo) and convenient (~15min/mo).

Actual Budget is an open source budgeting application. I run it on my personal computer, but if you’re not tech savvy you can pay for the cloud-hosted version for ~$1.50/mo.

I recommend using the SimpleFIN bridge to automatically import transactions (this is the only paid part, at $15/yr).

Optional techie stuff for added convenience:

Setup

Step 1: Configure tools

Step 2: Establish targets

Sample allowances

Step 3: Determine categories

Categorize your anticipated expenses within one of the budget groups:

Sample budget categories

Categorization tips

It’s good to be exhaustive with Fixed expenses because they improve month-to-month stability. The Flex expenses are mostly useful for tracking expenses over time, since anything that doesn’t go in there will go into Other. Tracking Flex expenses helps to calibrate budgeting, since you can set the amounts at the start of the month to be a rolling average (or last month’s value) to help estimate how much will be left over, but it’s a tradeoff of tracking overhead vs predictive accuracy. When in doubt, just pick the things that are easiest to automate rules for (e.g. gas stations, grocery stores, etc).

Put infrequent but known expenses (eg car registration) as Fixed expenses. My preference is to divide it evenly across the months and carryover the balances after each month, but you could also schedule the full value.

Monthly routine

At the start of every month go through these steps for the previous month:

Sample budget after reconciliation

In the example above you can see that Aladdin and the household went over budget. Oops! They’re carrying over a debt now and should dial it back next month.

Additional tips

There are a few knobs you can play with to help align incentives:

Allowances also lend themselves well to fancy financial decision making like joint purchase auctions.


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