Does this calculator tell me if I was overcharged?

No. It shows the arithmetic a CAM reconciliation normally follows and compares the result with the balance on your statement. A difference means the numbers do not match; it does not show the landlord is wrong. What counts as an operating expense, how the share is defined, and whether fees sit inside a cap all depend on your lease.

Where do I find the numbers?

The expense pool, any management fee and your share are usually on the reconciliation statement. Your pro-rata share or square footage is usually in your lease. Your estimated payments are your monthly CAM estimate times the months in the period.

How is this different from a LeaseGuard audit?

The calculator only does arithmetic on the numbers you type and cannot see your lease. A LeaseGuard audit reads your lease and your reconciliation statement, checks the statement against lease terms such as exclusions, caps and fee limits, and shows the source page for each item.

CAM Reconciliation Calculator

Work out your share of the year's common area costs and the balance you would expect, then compare it with the number on your statement. It runs in your browser: nothing you type is sent or stored, and no upload is needed.

Enter your numbers

Total operating expenses for the year

The expense pool on the statement, before your share is applied.

Management or admin fee (optional)

The percentage your statement shows, if any.

The expense total above already includes that fee.

How is your share defined?

A percentage Square footage

Your pro-rata share

Estimated payments you made for the year

Your monthly CAM estimate x the months covered.

Balance shown on the statement (optional)

Amount due as a positive number; a credit as a negative number.

Optional: compare with a CAM cap

Your prior-year CAM total

Cap on annual increase

Caps differ: some cover only controllable expenses, some are cumulative. This is a simple total-to-total comparison.

Enter your expenses and share to see the calculation.

How the calculation works

Start with the operating expenses for the year (the pool).
Add the management or admin fee if it is charged on top of the pool: pool = expenses + expenses x fee %.
Apply your share: your share = pool x your pro-rata %. If your lease defines the share by area, the percentage is your square feet divided by the building's.
Subtract your estimated payments: balance = your share - payments. Positive means you owe; negative is a credit.

Amounts are rounded to the cent at each step. Statements sometimes round the share percentage, which can move the result by a few dollars on large pools.

What this calculator assumes

The expense total you enter is the amount your lease allows to be shared. It does not check which expenses belong in it.
Your share is a fixed percentage for the whole year. Leases with gross-ups, caps on specific categories, base years, or occupancy adjustments need more than this.
The optional cap check compares totals only. Many caps apply to controllable expenses, and some are cumulative.
It is not legal or accounting advice. Deadlines and rights to question a statement depend on your lease and applicable law.

When the numbers do not match, or you cannot check them

A calculator cannot tell whether a line item is allowed under your lease. A LeaseGuard audit compares your reconciliation statement with your lease: exclusions, management-fee limits, caps and the share definition, with the source page for each item. The preview is free; the full report is a one-time $49 for one year or $149 for two to five years, and includes an editable dispute-letter draft.

Upload your lease and statement

Not sure what an audit includes? See a fictional sample report or read how automated lease audits work.

Questions

Does this calculator tell me if I was overcharged?: No. It shows the arithmetic a CAM reconciliation normally follows and compares the result with the balance on your statement. A difference means the numbers do not match; it does not show the landlord is wrong. What counts as an operating expense, how the share is defined, and whether fees sit inside a cap all depend on your lease.
Where do I find the numbers?: The expense pool, any management fee and your share are usually on the reconciliation statement. Your pro-rata share or square footage is usually in your lease. Your estimated payments are your monthly CAM estimate times the months in the period.
How is this different from a LeaseGuard audit?: The calculator only does arithmetic on the numbers you type and cannot see your lease. A LeaseGuard audit reads your lease and your reconciliation statement, checks the statement against lease terms such as exclusions, caps and fee limits, and shows the source page for each item.