A personal financial forecast is a simple model of the next few years: income, bills, debts, savings, and dated life events on one timeline. Keep one baseline that matches today, then copy it whenever you want to test a raise, a move, or a big purchase.
Last month's spending report is a clue. It is not a plan. A plan says what happens if rent rises, a raise lands, or you buy the car. This is for people who are tired of recaps and ready for a working sketch of the next few years.
You will see what a simple model needs, what it does not need, and how to keep it alive without turning into a full-time analyst. Direction first. Decoration later.
Knowing you spent $180 on dining last month is fine. Knowing what happens to next year if dining stays there and daycare starts is different. One is history. The other is a decision tool.
You do not need fifty tabs. You need income, spending, debts, savings, and a few timed events on one timeline you trust.
A recap answers “where did February go?” A model answers “if rent jumps $300 in August and we keep the same savings rate, what does next December look like?” Those are different jobs. Mixing them up is how people feel informed and still get surprised by a choice they already half-made.
The model does not need to be pretty. It needs to be honest about paydays, bill dates, and the big rocks: housing, debt payments, childcare, and the savings you claim you care about. If those pieces are wrong, the chart is theater.
Start coarse on purpose. One income line. A handful of expense groups. Debts with balances and rates. Accounts you actually use. Then add the next decision you are debating. A model that is 80% right and open weekly beats a perfect workbook you last touched in January.
Baseline, then what-if
Baseline
Income, fixed bills, debts, and savings you actually run today.
Name one change
Raise date, purchase, childcare start, or debt payoff order.
Compare cash and goals
Does runway hold? Does the goal date move?
Put in the numbers that change outcomes. Pay. Rent or mortgage. Debt payments. Savings rate. Known life events. Skip decorating every coffee purchase for now. Detail can come later. Direction comes first.
Timed events are where models earn their keep. A raise on the 1st of next quarter. A car payment that ends in fourteen months. Daycare that starts in September. A wedding weekend that pulls $12,000 in June. Without dates, you are averaging life into a mush that never matches how cash actually moves.
A forecast is an estimate, not a promise. Past year three, small assumptions like the size of a raise or a few points of inflation a year move the answer more than any coffee line, so read the far end as a range.
Keep a baseline that mirrors today. When you want to test a move, a payoff push, or a lower spend year, duplicate the baseline and change one lever. If you rewrite the only copy every time you brainstorm, you lose the “compared to what” that makes the chart useful. Two named scenarios beat one sacred file you are afraid to touch.
Update the baseline when reality changes, not every time you daydream. New salary on the 1st. Rent hike. Debt paid off. Those belong in the main file. “What if we bought the nicer car” belongs in a duplicate you can throw away. That split keeps the model useful instead of sacred and stale.
Share the picture when two people need to decide. Two mental models of “we can afford it” will disagree forever. One timeline with the raise, the rent, and the purchase date on it gives you something to point at. The argument gets shorter even when the answer is no.
Flan is projection-first on purpose. You build a scenario with income, expenses, accounts, debts, life events, and big purchases. Charts show cash flow and net worth over years. You can save more than one projection and share it when two people need the same picture.
Recaps tell you where you have been. A model tells you where a choice leads. Keep it simple, keep a baseline, and test the big what-if copies instead of rewriting history in your head.
Once the picture is visible, the next step gets easier to pick. Test a first what-if with Model the raise first or What a big purchase costs.
Run your own numbers with the free inflation / real return calculator: Free inflation calculator: convert a nominal return to a real return, and see future sticker dollars vs buying power.
Flan is planning software, not a bank, broker, or licensed advisor. Nothing here is financial, tax, or legal advice.
Read more Flan Files at theflan.app/blog.
