Lease Extension Calculator
When your lease is ending, the real question is never just “what is the new rent” but “is extending cheaper than moving once every fee is counted?” This calculator totals both sides: the full cost of extending (rent over the term with annual increases, extension fees, deposits) against the full cost of moving (market rent plus moving costs, deposits, broker and application fees).
You get a 12-month comparison, a break-even point, 3/6/12-month timelines, and a plain-English recommendation. Note: an earlier version of this page shipped with a broken script, so its calculator did nothing at all; this rewrite fixes that with the same math.
Extend or move? Full cost comparison with break-even and timelines.
Extension
Moving
Estimates for decision support, not financial advice. Annual increases compound at each 12-month boundary of the extension term. Confirm fees and terms with your landlord.
Worked example: $1,575 extension versus $1,650 market
Enter current rent $1,500, new rent $1,575, 12-month term, increase 3%, no fees; market rent $1,650, moving costs $2,000, new deposit $1,650, application fees $100. Extension year: 1,575 x 12 = $18,900. Moving year: 1,650 x 12 + 3,750 = $23,550. Annual savings: $4,650, so the recommendation is Extend the lease. Below market: $75.00 (4.5%). Break-even: 3,750 / 75 = 50 months. Verified against the calculator.
How the comparison is built
Extension total = extension fee + new deposit + rent summed over the term (the annual increase compounds at each 12-month boundary).
Moving total = market rent x 12 + moving costs + new deposit + broker fee + application fees.
Annual savings = moving total – extension total. Positive favors extending; within $500 either way is scored similar cost; otherwise moving wins. The break-even divides the upfront moving cost by the monthly rent difference.
What competing calculators miss
The only same-intent calculator on this keyword multiplies rent by months and adds a fee, then stops. It never asks what moving costs, never computes a break-even, and never makes a recommendation. This calculator prices both decisions side by side across 3, 6, and 12-month horizons. Note the trap the timelines expose: a lower monthly rent can still lose if the new term is much longer, because the comparison is total cost, not monthly cost.
Frequently asked questions
Should I extend my lease or move?
Compare the 12-month all-in cost of each option, not the monthly rent. If extending saves money after counting moving costs, deposits, and fees, extend.
What is the break-even point?
Upfront moving cost divided by the monthly rent difference. If moving costs $3,750 upfront and saves $75 a month, it takes 50 months to pay off.
How do rent increases during the extension work?
The tool applies your annual increase percentage at each 12-month boundary of the extension term, compounding on the current rent.
Is this the UK lease extension premium calculator?
No. UK leasehold extensions value the freeholder’s interest under the 1993 Act, including marriage value below 80 years remaining, which needs a professional RICS valuation. This tool compares extending a rental lease against moving.
What costs do people forget when comparing?
Application and broker fees, the new deposit (often due before the old one is returned), overlap rent, and time off work to move. Enter all of them on the moving side.
Why did the old version of this page not calculate?
Its script contained an encoding defect that stopped the whole calculator from loading. This version was rewritten with the same formulas and verified working.