First Home True Cost Calculator

First-time buyers often underestimate the year-one cost. A 300,000 first home: 30,000 deposit, 5,000 transfer tax, 1,500 legal, 500 survey, 1,000 arrangement, 15,600 mortgage (12 months), 3,600 maintenance budget, 2,000 insurance and tax — 59,200 cash out in year one alongside starting without furniture or a working budget. Running the real number before committing makes the decision honest.

A worked example

Try the defaults: deposit of 30,000, upfront costs of 8,000, annual mortgage of 15,600, annual running costs of 5,600. The tool returns 64,200.00. You can adjust any input and the result updates as you type — no submit button, no reload. That's the real power here: seeing how sensitive the output is to one or two assumptions.

What moves the number most

The result responds to Deposit, Upfront Costs (tax, legal, fees), Annual Mortgage (Y1), Annual Running Costs, and Furniture & Setup.

The formula behind this

Sum of all year-one cash outlays. Deposit and upfront are one-off; mortgage, running, furniture are annualised or one-off depending on setup. Everything the calculator does is shown in the formula box below, so you can check the math against your own spreadsheet if you want.

Budgeting for the milestone

One-off life events have a habit of spreading — a wedding that "costs 15,000" routinely ends at 20,000 once related expenses are tallied. Use this tool to build the realistic figure, then add 10–15% for the items you haven't thought of yet.

What this doesn't capture

Life events generate side costs the figure doesn't include: time off work, lost income, travel for others, aftercare. Add 10–15% to the direct number as a buffer; the items you haven't thought of usually fill most of it.

Common scenarios

This calculator proves most useful when:

• Comparing affordability across different property prices or deposit sizes
• Planning savings timelines for year-one outlay
• Testing how changes to mortgage amount or running costs affect total spend
• Building a household budget that accounts for all first-year expenses at once
• Communicating realistic costs to partners or family members involved in the decision

Limitations of this result

The calculator models year-one costs only. It does not include:

• Future maintenance or repair costs beyond the first year
• Property value changes or market conditions
• Tax relief, allowances, or other tax implications
• Refinancing, overpayment fees, or early repayment penalties
• Inflation or interest rate shifts after year one
• Costs of selling or moving home

The output is for illustration and budgeting purposes only. It models a snapshot of year-one cash flow, not a full financial picture or projection.