How a general lease payment is worked out
A lease is a form of financing: instead of borrowing the whole asset cost, you are only financing the part of it you expect to use up, the difference between the cost and what the asset should still be worth at the end, called the residual value. The exact method treats a lease the same way a textbook treats any annuity problem: the present value of every future payment, plus the present value of the residual received back at the end, must equal the asset cost today. Rearranged for the payment, that gives one formula:
The calculator's own defaults make this concrete: an asset costing 30,000, expected to be worth 12,000 after 36 months, leased at a 6% annual rate, produces a payment of 607.59 a month. Over the full term that totals 21,873.42 paid, of which 18,000.00 is the depreciation you were always going to pay for (the 18,000 gap between the cost and the residual) and 3,873.42 is the finance charge for spreading it out.
The money-factor shortcut, and why it lands slightly differently
Many lease quotes, especially for vehicles, are built from a simpler shortcut rather than the exact method above. It splits the payment into a depreciation portion, the cost minus the residual divided evenly across the term, and a finance portion, calculated as the cost plus the residual, multiplied by the monthly rate, divided by two:
On the same numbers, 30,000 cost, 12,000 residual, 36 months and 6% a year, that shortcut gives 500.00 depreciation plus 105.00 finance, a payment of 605.00. It is close to the exact 607.59 but not identical, because it charges the finance rate evenly against the average of the starting and residual balances rather than discounting the true payment stream the way the exact method does. The gap is small at modest rates and terms and widens as either climbs, so this calculator shows the exact figure as the headline and the shortcut alongside it as a labelled comparison, never the other way round.
What the residual value means, and who carries the risk
The residual is a forecast, made at the start of the lease, of what the asset will be worth once the term ends, and it drives the payment directly: raise the residual and less of the cost needs financing, so the payment falls; lower it and the payment rises. Who bears the cost if that forecast turns out wrong depends on the type of lease. In a closed-end lease, the leasing company sets the residual and absorbs the loss if the asset is actually worth less at handback, which is why closed-end payments sit a little higher, to price in that risk. In an open-end lease, common for commercial vehicle and equipment fleets, the lessee guarantees the residual and owes the difference if the asset falls short of it at sale, in exchange for a lower payment along the way. Neither structure is universally better; it is a straightforward trade between a lower payment now and carrying the valuation risk later.
Where general leases run, and where the conventions change
This calculator's formula applies to any leased asset with a fixed cost, term, rate and residual: office and IT equipment, manufacturing machinery, commercial vehicles bought for a business rather than a single car, and fit-out or fixtures leased alongside a unit. Commercial property leases are the one common exception worth flagging on their own: rent is usually quoted per period rather than amortised against a residual, and long leases often carry scheduled or index-linked rent reviews instead of one fixed payment for the whole term, so the maths here does not transfer directly to a property lease.
What happens when a lease ends
A lease agreement fixes what options exist at the end, and the standard menu has three entries. Returning the asset closes the lease with nothing further owed, assuming it meets whatever condition and usage terms were agreed at signing. Buying the asset outright for the residual value turns the lease into ownership at a price fixed from day one, which is worth comparing against what the asset would actually be worth on the open market by then. Extending or renewing the lease, often at a lower payment once most of the depreciation has already been paid for, keeps the asset in use without either of the other two choices. Which option makes sense depends on whether the business still needs the asset, what it is really worth by then, and whether newer equipment would serve better than renewing an ageing one.
Questions people ask
Is leasing cheaper than buying?
Not usually in total cash terms; the "Buying outright versus leasing" chart above typically shows the total of lease payments running above the outright cash price, since the finance charge is the price of spreading payments out and not carrying the residual's value yourself. Leasing wins on cash flow, a lower amount out of the door now and each month, and on not being stuck owning a depreciated asset later, which is a different question from total cost.
What is a residual value, in plain terms?
It is the value the asset is expected to still have once the lease term ends, agreed at the start rather than measured at the end. A higher residual lowers the monthly payment because less of the asset's value needs financing along the way; it also means more value is still tied up in the asset when the lease finishes, which is why who bears the risk of that forecast being wrong matters.
What is the difference between a closed-end and an open-end lease?
In a closed-end lease, the leasing company sets the residual and absorbs any shortfall if the asset is worth less than expected at handback, so payments are priced a little higher to cover that risk. In an open-end lease, the lessee guarantees the residual and owes the difference if the asset sells for less, in return for a lower payment during the term. Most consumer vehicle leases are closed-end; commercial equipment and fleet leases are more often open-end.
Why does the money-factor estimate not match the exact payment?
The money-factor shortcut charges the finance rate evenly against the average of the starting cost and the residual value, rather than discounting the actual stream of payments the way the exact annuity method does. The two are built on different assumptions about how the finance charge accrues, so they land close together but rarely identical; the gap grows at higher rates and longer terms.
Does this calculator work for a commercial property lease?
Not directly. Property leases are usually quoted as a rent per period rather than a cost amortised against a residual, and long leases often include scheduled or index-linked rent reviews rather than one fixed payment for the whole term. This tool is built for equipment, machinery and vehicle-style leases with a fixed cost, rate, term and residual.
What can I do when a lease ends?
Standard options are to return the asset with nothing further owed, buy it outright for the agreed residual value, or extend or renew the lease, often at a reduced payment. Which is worth taking depends on what the asset is genuinely worth by then against the fixed residual price, and whether the business still needs that asset or would be better served by newer equipment.
Can I use this to check what asset cost I can afford?
Yes, the "Find maximum cost" tab does exactly that: give it the residual value you expect, a target monthly payment and a term, and it solves algebraically for the most an asset can cost while keeping the payment at that target, the same underlying equation run in reverse.
These figures are estimates for a general fixed-rate lease, not financial, tax or legal advice. A real lease agreement can carry fees, insurance requirements, usage limits and end-of-term conditions this calculator does not see, so check the actual agreement, or ask the leasing company, before signing anything.