The car envelope
$195 a month. Set Mar. 7, 2026.
One car between two people: a 2013 Corolla with 141,000 miles on it, bought used in 2019 and paid off since 2022. Roughly 780 miles a month, most of it three round trips a week to the hospital and back. There is no car payment on this page and that single absence is worth more than every other line in this budget put together.
What the envelope covers
| Cost | Monthly |
|---|---|
| Fuel, about 24 gallons | 106 |
| Hospital parking pass, per day worked | 65 |
| Washes, wipers, fluids, air | 24 |
| Envelope | 195 |
What it does not cover, and why
Insurance, registration, tires and maintenance are all sinking funds, not envelope lines. The test we use is whether the cost arrives on a schedule the month knows nothing about. Fuel is monthly and roughly level, so it is an envelope. A timing belt is $700 once, at an unknown time, so it is a pot you fill in advance.
Putting maintenance in the envelope was the original arrangement and it failed in the most predictable way: for eleven months the car envelope looked generous, and in the twelfth the alternator went and the month was destroyed. Nothing about that pattern is a budgeting insight; it is just what averages do to you when you spend them monthly.
July 2026 is the worked example. Four tires, $402, mounted and balanced. The car envelope that month finished $18 over on fuel and wipers, exactly as it would have in a month with no tires, and the $402 came out of a pot that had $588 in it. The July issue has the ledger.
The mileage question
At 141,000 miles the reasonable expectation is a $1,300 year at some point in the next three: water pump, struts, the catalytic converter if we are unlucky. The maintenance fund accrues $110 a month against exactly that, and if the car reaches 200,000 without needing it we will have been wrong in the direction that leaves us with money.
We do not have a replacement plan and we are not saving for one, which is the least defensible position on this site. The honest version is that a used Corolla in this condition is worth about $6,800 and a replacement is not a decision we can currently afford to make well, so we are running it and putting the difference in the emergency fund. Ask again in March.