A net worth tracker for UK households, projected years forward

A tracker that only records today is a diary. Useful, but it never answers the question you actually have: will we be in a materially better position in five years, or are we running hard to stand still. Every debt is amortised properly, so the mortgage balance in year seven is what a real repayment schedule at your rate and term produces, not a straight line between two points. Dated changes you have planned, a pay rise, a rate change, a payment that stops, move the numbers from that month onward. The result is a net worth figure for every future period rather than one for now.

The net worth forecast steps between daily, monthly and annual periods. For a single date, use the As at date on the input screen: pick any day and every card there, net worth, assets, liabilities and the cash balance, is projected to it, which is the natural way to answer “where will we be when the fixed rate ends”. Net worth comes back with its leverage, debt as a share of assets, beside it.

Monthly is for the next couple of years, where the timing of a single event is visible. Annual is for the long view, out to the ten-year horizon every forecast runs. That horizon is a product decision, and here is why it stops at ten years.

The stepper at the top of the forecast chooses the period, and arrows beside it move through time. A second choice sits inside the chart card and decides what is plotted. Balance is the net worth figure itself, one bar per period, and it is where the depth is. Movement is the other question, the change from one period to the next. The Options button opens how far into the balance the chart goes. Breakdown stacks the assets against the liabilities behind it and runs the net worth line through the middle, so a rising line reads as a house being bought and a mortgage being repaid rather than one number going up. Detail goes further again and gives every holding and every debt its own series, so you can tell which one is moving the total.

Where the chart carries named series, tap one in the legend and it comes forward with the rest faded behind it. Nothing is removed and the axis does not move, which is the point: the question a net worth chart exists to answer is how the house compares with the pension, and you can only see that while both are still drawn to the same scale.

The statement is the part you will actually read. Its rows are Assets, Liabilities, Net Worth, Movement, and a debt-to-asset ratio. Movement is the change from the period before, the number that tells you whether a good month was actually good. The ratio shows the shape of the balance sheet rather than its size, and it moves most reliably in your favour as a mortgage is paid down.

Net worth is also the only statement with group subtotal rows. Fixed assets total separately from current assets, so you can see how much of your position is a house you live in and how much is money you could reach this week.

There is deliberately no subtotal column, and if you have used a tool that adds one, treat that as a bug rather than a feature. Cashflow and profit & loss are flows, so a year total is a real number. Net worth is a stock. Adding January's net worth to February's produces a figure that means nothing.

Any line can be opened. The Analysis tab drills into each holding: properties with loan-to-value, equity and the secured debt against them; loans and debt with the rate, the term remaining and the total interest; pensions; savings and investments; vehicles and everything else. Properties, debts, pensions and savings each open an analysis screen of their own.

There are six asset classes and that is the complete list: property, savings, investments, pensions, vehicles, and other. Vehicles are the interesting one. A car is not a store of value, so CrestCast depreciates it on a ladder based on its year of manufacture rather than holding it at what you paid. Most trackers let a car sit in your assets at purchase price for years, which quietly flatters the total.

Debts are mortgages, loans, credit cards and student loans, each modelled on its own terms rather than as a generic balance. A mortgage knows its rate, its term and what happens when a fixed rate ends. A credit card has its own simulator with promotional periods. The debt payoff planner goes into how each of those four is modelled in detail.

Two of those lines are a deliberate editorial choice, and reasonable people disagree with it. Most net worth trackers leave the pension out, on the grounds that you cannot spend it, and leave the student loan out, on the grounds that it is not a normal debt: it is written off eventually, it is collected as a percentage of income above a threshold, and it does not follow you the way a loan does. CrestCast shows both, by default, because a balance sheet that hides your largest asset and your longest-running liability is not a balance sheet, it is a selective one.

A defined-benefit scheme goes in the same way. Type the transfer value your scheme has given you and it is used exactly as it stands, for you and for a partner or another adult in the household. Leave your own blank and the app puts an estimate in from your years of service and your salary, and marks that row as an estimate for as long as it is one, so you always know which of the two you are reading.

Take a household with a home at £340,000, a £220,000 mortgage at 4.6% with twenty-two years to run, £14,000 in a stocks ISA, a £95,000 pension pot, a car worth £11,000 and £6,000 in savings. Assets £466,000, liabilities £220,000, net worth £246,000, and a debt-to-asset ratio just over 47%.

Now put £400 a month into the ISA and £450 a month into the pension between you, and let the mortgage run. Five years out the mortgage is down to roughly £187,500, because that is what a real amortisation schedule does at that rate over that term. That figure is settled by the schedule rather than by an assumption. The asset side is not: the ISA and the pension build from the contributions landing and then grow at the rates you set, and the house moves at the property growth rate you give it. The car is the exception, depreciating on its ladder whatever else you do.

So a five-year net worth is two things added together, and it is worth reading them apart. Debt repaid and money actually put aside is arithmetic. Everything else is a growth rate you chose, and changing one changes the answer, which is the whole reason you get to set them rather than inherit someone else's.

Selling something is where naive trackers fall over. They let you delete the asset, and the debt attached to it hangs around, or the money appears in savings with no date on it. In CrestCast an asset sale is a dated event: the proceeds land in cash in the month of the sale, the mortgage secured on that asset is settled out of those proceeds on the same form, and the asset stops contributing from that month onward. Downsizing, selling a rental, selling the car, all of it lands as one coherent set of numbers rather than three manual edits you have to keep consistent.

You can also change whose balance sheet you are reading without re-entering anything. Switch between your own position, your partner's, the joint accounts on their own, each child with an account of their own, or everything combined. Couples who keep some money separate get a combined total without merging two lives into one pot. More on that on the families page.

Set a future date on the input screen and every balance moves to what it will be then: cash, savings, assets and debts. Tap the information marker on a line and a panel opens with the arithmetic that got there. On a mortgage that is the anchor balance you entered, then each payment between now and the date you picked, split into interest and capital, with the closing figure at the bottom.

Three details are worth knowing, because they are what makes it worth reading rather than decorative. The panel adds up its own lines and, if they do not reconcile with the figure on the row, it prints a line saying so instead of quietly making the total fit. Every group of lines names the input it came from, with the anchor figure tappable straight through to the screen where you typed it. And where a figure has no honest breakdown behind it, an interest-only debt being the plain case, the row states that and gives the reason rather than showing a marker that opens nothing. So the answer to “where has that number come from” is either one tap away or explained on the row, and it is always traceable back to something you entered.

The balances are the ones you enter and they are as current as you keep them, because CrestCast does not link to your accounts. On a projected balance sheet that matters less than it sounds, since the mortgage schedule and the contributions drive most of the movement, and what you get for it is a model holding exactly what you chose to put in it.

An investment is a single balance, not a portfolio. No tickers, no funds, no asset allocation, no live prices. A sale runs through the forecast gross, with no capital gains tax deducted and no inheritance tax anywhere, so a disposal you expect to be taxed is worth working out alongside.

And the projection is a single line, not a range. It runs your inputs forward deterministically and shows you one path. It is a model of your decisions, which is the useful thing, but it is not a statement about what will happen. Read it as “this is what these choices produce”, not as a prediction.

Nearly everyone who cares about this has tried the spreadsheet. A tab with assets down one side, debts down the other, a date at the top. It works for a while. Then the retyping starts: seven balances, every couple of months, from seven different apps and statements. The gaps get longer, the last column gets staler, and at some point you stop.

Projecting it forward is a different order of problem. By hand you need an amortisation schedule for every debt, month by month, at the right rate for the right term, rebuilt each time a rate changes or you overpay. You need contributions landing on the right months, and the sale of the house settling the mortgage out of the proceeds in the correct month. Any one of those is a Saturday afternoon. Keeping all of them right, every time something changes, is what nobody sustains.

That is the whole argument for a tool here. The balance sheet is easy; the schedule underneath it is not. The same reasoning applies to the profit and loss side of the picture.