Most owners of a letting agency know roughly how busy they are. Far fewer know whether they are actually making money on each managed property, where profit is leaking, or which part of the business is growing. Key performance indicators, or KPIs, answer those questions in a few numbers you can check every month.
This guide covers the 7 KPIs that matter most for a letting agency, how to calculate each one, and what to do when a number moves the wrong way.
Why KPIs matter more than turnover
Turnover tells you how much came in. It does not tell you whether prices cover costs, whether time is being used well, or whether cash will be there next month. A letting agency can grow turnover and still make less profit if costs grow faster. KPIs show you the drivers behind the result, early enough to act.
The 7 KPIs for a letting agency
1. Units managed
How to calculate it: Properties under management
Your recurring base.
2. Average fee per unit
How to calculate it: Fee income ÷ units
Shows pricing strength.
3. Direct cost % of sales
How to calculate it: Direct costs ÷ fee income
The margin check.
4. Arrears
How to calculate it: Rent overdue across the portfolio
Protects landlords and fees.
5. Void days
How to calculate it: Days properties sit empty
Lost rent and fees.
6. Certificates due
How to calculate it: Certificates expiring in the next 30 days
A compliance risk.
7. Landlord retention
How to calculate it: Landlords kept ÷ landlords at start of year
Your recurring income.
Interpreting these measures in practice
Track managed properties that are active and fee-paying, not just signed instructions. Pair average fee and arrears with void periods, maintenance requests, compliance workload and staff time per property. A growing portfolio can reduce margin when new homes need disproportionate support. Monitor client retention and tenant issues as quality signals, and compare contractor payments with client-money receipts by date. Use the numbers to review fee structure and workload before adding more properties.
Start with the profit basics
Alongside the industry KPIs above, every owner should check four headline figures each month:
- Total income for the month and year to date
- Total costs, split into direct costs and overheads
- Net profit and operating margin
- Lowest cash balance in the next 12 weeks, from a cash flow forecast
If net profit is falling while turnover rises, look at the cost KPIs first. If cash is tight while profit looks fine, look at unpaid invoices.
An example month (illustrative figures)
Say a letting agency takes £8,000 in a month and spends £2,900 on the direct costs of delivering the work. Gross profit is £5,100, a gross margin of 64%. If last month the margin was several points higher on similar turnover, something has changed in prices, costs or the mix of work, and the KPIs above show where to look. These figures are illustrations only: use your own.
What to do when the numbers slip
- Growing fully managed properties
- Charging for extra work instead of absorbing it
- Buying a small rent roll
- Reviewing fees every year
Pick one action at a time, so you can see what made the difference. If you are asking what the business could pay you, read how much a letting agent earns in the UK.
How to review your KPIs every month
1. Update your records for the month: managed propertys, sales, costs and invoices. 2. Compare each KPI with last month and the same month last year, so seasonal swings do not mislead you. 3. Pick the one number that moved most in the wrong direction and find out why. 4. Decide one action for next month, such as a price change, a rota change or chasing a debtor. 5. Check the result at the next review.
Fifteen minutes a month on this routine is enough to catch most problems while they are still small.
Common mistakes with KPIs
Tracking too many numbers. Pick the handful that drive your profit and review them consistently.
Looking at one month in isolation. Trends matter more than single results.
Not acting on what you find. A KPI that never changes a decision is just a number.
Keeping figures in your head. Write them down, or let a spreadsheet calculate them, so nothing is guessed.
Run the numbers on your own business
The **Property Management Business Management System** tracks every managed property, cost, invoice and VAT return, and works out your profit, margin and key figures automatically on a one-page dashboard. It costs £15 once, with no subscription. Before you open, work out your start-up costs with our free property management start-up calculator. For the full start-up walkthrough, read our guide on how to start a letting agency.
Frequently asked questions
What is the most important KPI for a letting agency? Gross margin, because it shows whether your prices cover the direct cost of each managed property. If it is wrong, growth only makes things worse.
Which KPIs should a new letting agency track first? Start with units managed, average fee per unit and direct cost % of sales. They are quick to work out and show straight away whether your pricing and capacity are right.
Can KPIs help me set prices? Yes. If your margin or rate per managed property is below target, your prices are too low for your costs, however busy you are.
What is a good gross margin for a letting agency? There is no single benchmark, because margins depend on your mix of work, location and whether you pay staff. The useful test is your own trend: a margin that holds steady or rises as you grow is healthy, and a falling one needs action on price or costs.
How often should I check my KPIs? Monthly for most figures, and weekly for cash and unpaid invoices.
Do I need software to track KPIs? No. A spreadsheet that calculates the figures from your records works well for most small businesses and avoids monthly fees.