Revenue beat budget by a healthy margin, but did the hotel keep its share of that extra revenue as profit? Flow-through is the ratio that answers it. Owners and asset managers ask about it in monthly reviews, and it is easy to get wrong when the inputs aren't lined up. This guide defines flow-through, shows how it relates to a flexed budget, and works through a fictional example.
The flow-through formula
flow-through = (actual GOP − comparison GOP) ÷ (actual revenue − comparison revenue)
The comparison is usually the budget or the same month last year. Use GOP and total operating revenue for the whole hotel, or departmental profit and departmental revenue for one department. The two inputs must cover the same period and the same scope.
When revenue is above the comparison, flow-through tells you what share of the extra revenue reached GOP. When revenue is below, the same formula is often called retention or "flow-through on the decline": it shows what share of the lost revenue came out of GOP. A lower figure on the way down means costs were cut in step with revenue.
The ratio breaks down when the revenue change is very small: dividing by a number near zero produces large, meaningless percentages. Report the dollar changes alongside it.
Flexed budget: the companion view
Flow-through tells you how much of the revenue change reached profit; a flexed budget tells you what profit should have been at the revenue you actually achieved. The method below is the one the Department Flow-Through & Forecast Tool uses:
- For each budget cost line, set its variable share: the part of the cost that moves with revenue (0% for a fixed contract, a higher share for cost of sales or hourly labor).
- flexed cost = budget × (1 − variable share) + budget × variable share × (actual revenue ÷ budget revenue). Operated departments flex on their own revenue; undistributed lines flex on total revenue.
- flexed profit = actual revenue − Σ flexed costs.
- expected flow-through = (flexed profit − budget profit) ÷ revenue change: what the budget's own cost behavior says should have reached profit.
- flex variance = actual profit − flexed profit. A negative flex variance means costs ran above what the revenue level explains: rate, productivity or spending.
Every property draws the variable and fixed line differently, so write the variable shares down where the reader can see them.
Worked example: Sample Resort, one month (fictional)
All figures are fictional sample data.
| Sample Resort (fictional) | Budget | Actual | Change |
|---|---|---|---|
| Total operating revenue | $2,000,000 | $2,150,000 | $150,000 |
| Variable costs | $900,000 | ||
| Fixed costs | $400,000 | ||
| GOP | $700,000 | $760,000 | $60,000 |
Flow-through: $60,000 ÷ $150,000 = 40.0%. Of every extra dollar of revenue, about 40 cents reached GOP.
Flexed budget. To keep the arithmetic short, this example groups the fictional budget costs into one line of $900,000 with a 100% variable share and one line of $400,000 with a 0% variable share, flexed on total revenue. Flexed variable line = $900,000 × ($2,150,000 ÷ $2,000,000) = $967,500; the fixed line stays at $400,000. Flexed GOP = $2,150,000 − $967,500 − $400,000 = $782,500. Expected flow-through = ($782,500 − $700,000) ÷ $150,000 = 55.0%, against actual flow-through of 40.0%. Flex variance = $760,000 − $782,500 = -$22,500.
So GOP beat the original budget by $60,000, but at that revenue level it should have beaten it by $82,500. The $22,500 shortfall is the conversation for the monthly review: which departments spent more than their volume justified.
A decline month. In another fictional month revenue comes in at $1,850,000 against the same $2,000,000 budget, and GOP at $620,000. Flow-through on the decline = ($620,000 − $700,000) ÷ ($1,850,000 − $2,000,000) = -$80,000 ÷ -$150,000 = 53.3%: a little over half of the lost revenue came out of GOP.
For the KPI definitions behind GOP and RevPAR, see the hotel KPI template guide; for setting the budget you are measuring against, see the resort annual budget template guide.
Tips for reporting flow-through
- Show it by department as well as for the hotel, so a strong Rooms result doesn't hide a weak F&B month.
- Show month and year to date. A single month can swing on timing.
- Always show the dollar changes next to the percentage.
Choosing the comparison
Flow-through against budget tests the plan: did the team convert extra business into profit at the rate the budget assumed? Flow-through against last year tests the operation over time, but last year may have had a different room count, a renovation or a different business mix, so note anything that makes the two years hard to compare. You can show both. Whichever you use, use the same comparison for revenue and GOP, and the same scope (whole hotel or one department) on both sides of the division.
It also helps to agree up front which costs the team treats as variable. Commissions, cost of sales and hourly labor usually move with business; salaried management, contracts and most undistributed costs move little in the short term. Writing that split down once makes the flexed budget, and the conversation about it, much shorter.