What is ALOS in hotels and what your average length of stay is telling you
The first owner I ever presented a monthly revenue pack to didn't ask me about RevPAR. He didn't ask about ADR. He skimmed past the channel breakdown and pointed at a number tucked in the bottom corner of the operational summary — the ALOS hotel figure for the month. It read 1.6 nights. He looked at me over the top of his glasses and said, "Why is that not a two?" I had no answer ready. I'd been treating ALOS as housekeeping trivia. He was treating it as a margin signal. He was right, and I was wrong, and it took me another two years to understand exactly why.
What ALOS actually means in 2026
ALOS stands for average length of stay. It is the average number of nights a guest stays at the property, across every distinct stay in the period you're measuring. One arrival equals one stay, regardless of how many nights that guest ends up booking. So a hotel with one guest staying five nights and one guest staying one night has an ALOS of three — not because anyone stayed three nights, but because total nights divided by total stays gives you three.
The reason this matters in 2026 — more than it mattered in 2010, and certainly more than it mattered in 2000 — is that the cost structure of running a hotel has shifted. Distribution cost is higher. Housekeeping cost per check-out is higher. Front-desk labour cost per arrival is higher. Each of those costs is paid per stay, not per night. Which means that for a hotel running an ALOS of 1.4, every cost is amortised over fewer nights than for a hotel running an ALOS of 2.4 — even if the two properties have identical RevPAR.
That's the quiet thing the ALOS hotel number is doing on your dashboard. It is the multiplier on every check-out-anchored cost in the building. And most operators are not reading it that way.
The ALOS formula (with two useful variants)
The headline formula is the simplest in the metric stack.
Total room nights sold is the same number you use in your RevPAR denominator's cousin — total occupied room nights for the period. Total number of stays is the count of unique arrivals, not the count of unique guests and not the count of room nights. One reservation that covers four nights counts as one stay. Two back-to-back reservations from the same guest count as two stays, unless your PMS has merged them.
Variant one: ALOS by segment
Aggregate ALOS hides the most important story in the number. Run the same calculation for each segment and the picture sharpens immediately. Corporate transient is usually short — often one or two nights. Leisure transient sits longer — two to three. Group and conference business runs three to seven. Wholesale, tour series and crew contracts can run longer again. The aggregate number is the weighted average of those, and it moves whenever the mix moves, regardless of whether the underlying segments have changed.
Variant two: ALOS by day-of-arrival
This is the variant most operators don't run, and it is the one that drives the best pricing decisions. Calculate ALOS separately for each arrival day of the week. The patterns are not subtle. Friday and Saturday arrivals at most leisure properties run materially longer than mid-week arrivals. Sunday arrivals at most corporate properties are short turnaround business. If you know your arrival-day ALOS curve, you know exactly where your minimum-stay walls should sit.
A worked example: 120-key urban hotel, one month
Take a typical 120-room urban property over a 30-day month. Run a clean calculation.
| Input | Value |
|---|---|
| Total rooms in the hotel | 120 |
| Nights in the period | 30 |
| Available room nights (120 × 30) | 3,600 |
| Total room nights sold | 2,700 (75% occupancy) |
| Total number of distinct stays | 1,420 |
| Implied ALOS | 1.90 nights |
An ALOS of 1.90 on a mixed-segment urban property is broadly normal. The interesting question is not the number itself. The interesting question is what would happen if that 1.90 became a 2.10 — through better minimum-stay walls on compression nights, smarter group sourcing, or a re-pointed contract mix. On the same 2,700 occupied nights, the number of stays would fall from 1,420 to roughly 1,285. That's 135 fewer check-outs over the month. Every one of those 135 avoided check-outs takes a housekeeping cost off the P&L, a front-desk arrival off the rota, and one of the most expensive moments in the operational day off the staff schedule.
Where ALOS breaks down — the failure mode most operators miss
The trap with the ALOS hotel number is that it can be moved by two completely different forces, and the two are not equally good news.
Force one is a genuine lengthening of the average stay — minimum-stay walls held on the right nights, better group mix, a leisure programme that converts longer breaks, a wholesale contract restructured into a higher-night-count series. This is the good kind of ALOS growth. It produces lower per-stay distribution cost, fewer check-outs, less housekeeping cost per occupied room, and a meaningful uplift to net RevPAR. I covered the distribution-cost side of this in OTA commission rates in 2026 — what hotels are really paying, which is the natural companion read.
This is why ALOS is never the whole picture — it has to be read alongside ADR and segment mix. RevPAR can mislead in the same way, which I explored at length in how to calculate RevPAR — formula, examples and the trap nobody talks about. The three metrics — ALOS, ADR and RevPAR — are siblings. They are not substitutes for each other.
What to do about it — a five-step ALOS playbook
Here is the workflow I run with properties when ALOS is the question on the table.
- Calculate ALOS by segment, every month. Aggregate ALOS is decorative. Segmented ALOS is operational. Once you can see corporate transient at 1.4, leisure transient at 2.3, and group at 4.1, the next move becomes obvious — and the segment that has drifted is the one to investigate.
- Map ALOS by arrival day of week. If your Friday arrivals run an ALOS of 2.4 and your Saturday arrivals run 1.2, your minimum-stay walls on Saturday-only bookings are doing real work — or should be. The arrival-day curve tells you where to fence and where to let the room go.
- Use minimum length of stay restrictions on compression dates. The classic example: a citywide event that compresses Saturday demand to near-100%. A two-night minimum on Saturday arrivals protects the orphaned Friday-or-Sunday inventory from being left unsold. This is the single most powerful ALOS lever in the daily revenue manager toolkit.
- Audit your contract and wholesale ALOS quarterly. A long-stay contract at a deep discount might look like a margin win on the housekeeping line and a loss on the rate line. Run the net-RevPAR maths before renewing. Sometimes the contract is genuinely accretive once cost-per-stay is included. Sometimes it is not.
- Report ALOS alongside ADR and net RevPAR. On every owner deck. Three columns, same row. The three numbers tell the truth together that none of them tells alone. If ALOS is up and ADR is down, you have a mix shift to explain. If ALOS is up and ADR is flat and net RevPAR is up, you have a real margin win and you should name it.
A real scenario — anonymised, but it happens every quarter
We pulled the ALOS by month. Two years earlier it had sat at 2.1. By the time we sat down it had drifted to 1.5. Nothing had collapsed — the property was occupancy-healthy, ADR was steady, RevPAR was within a couple of percent of plan. But the mix had shifted. A long-running corporate contract had wound down. Two leisure tour-series contracts had been allowed to lapse. The vacated nights had been backfilled with OTA transient — shorter stays, higher per-stay distribution cost, and twice as many check-outs over the same occupancy footprint.
Housekeeping cost was up because the number of check-outs was up. ALOS had been the underlying signal for six months. Nobody had been reading it.
The fix was not dramatic. The GM re-signed one of the leisure tour-series contracts at a slight rate concession. The revenue manager introduced a two-night minimum on Saturday arrivals through high season. A modest leisure-package programme was launched on the brand site, designed to convert single-night Saturdays into Friday-Saturday stays. Six months later, ALOS was back to 1.9. Housekeeping cost per occupied room was back inside the peer benchmark. RevPAR was up two percent. Net RevPAR was up four. The metric they had stopped reading had told them exactly what was happening the whole time. And forecasting which months would carry the mix-shift risk was the other half of that work — I covered the demand-signal side of that in hotel demand forecasting for revenue managers.
How ALOS fits inside a complete revenue programme
ALOS is a metric. Like every metric, it is a single instrument on the dashboard. The reason I treat it as essential rather than ornamental is that it is the only metric in the rooms-revenue stack that tells you something about the operational cost of the business. RevPAR tells you about the top line. ADR tells you about rate. GOPPAR tells you about profit after everything. ALOS sits in between — it is the operational lever that quietly determines how much of the gross revenue survives the journey to the bottom line.
The companion read on positioning ALOS inside the broader strategy is hotel revenue management strategies for 2026, which steps up a level and looks at how the metric layer feeds into the strategy layer. And for the comparative metric reading — RevPAR versus ADR versus GOPPAR — the most useful follow-on is ADR vs RevPAR vs GOPPAR — which one actually tells the truth.
FAQ
What does ALOS mean in hotels?
ALOS stands for average length of stay. It is the average number of nights per stay across the period you're measuring, calculated as total room nights sold divided by total number of distinct stays. One arrival equals one stay, regardless of how many nights are booked under it.
How do you calculate ALOS for a hotel?
Take total room nights sold in the period — the same number that sits in your occupied-room-nights line — and divide it by the total count of distinct stays. Stays, not guests, and not room nights. A back-to-back booking by the same guest counts as two stays. The result is your ALOS in nights, usually expressed to one decimal place.
Is a higher ALOS always better?
Usually, but not unconditionally. Longer stays mean fewer check-out cleans, less front-desk arrival load, and lower per-night distribution cost. The exception is when long stays come from deeply discounted contract business that crowds out higher-rate transient demand on compression dates. The honest read is ALOS alongside ADR and net RevPAR — never on its own.
What is a good ALOS for a city hotel?
It varies with segment mix and market, but a useful working range for a mixed-segment city hotel sits around 1.8 to 2.3 nights. Resorts run materially higher — three to seven nights is normal. Extended-stay properties and serviced apartments run higher again. The number on its own is not the signal. The trend over time and the breakdown by segment is.
How does ALOS affect housekeeping cost?
The most expensive housekeeping clean in any hotel is the check-out clean. A three-night guest costs you one full check-out clean plus two servicing cleans. A one-night guest costs you one full check-out clean per night. ALOS is the single biggest operational driver of housekeeping cost per occupied room. A lift in ALOS of half a night across an 80-room property typically takes a meaningful share off the housekeeping line over a year.
How does ALOS relate to minimum length of stay restrictions?
Minimum length of stay restrictions are the primary tactical lever revenue managers use to actively manage ALOS on demand-heavy dates. A two-night minimum on a Saturday arrival during a citywide compression event protects the shoulder nights from being orphaned and lifts the effective ALOS for the period. Used too broadly, MLOS restrictions cost you bookings. Used surgically on the right dates, they are one of the most powerful tools in the daily revenue manager toolkit.
Should ALOS be tracked by segment?
Always. Aggregate ALOS hides the most important story in the number. Corporate transient typically runs one to two nights. Leisure transient runs two to three. Group business runs three to seven. Wholesale and tour series can run longer again. A mix shift between segments often moves your aggregate ALOS without anything else changing — and the segment-level breakdown is the only way to see whether the move is a margin win or a margin warning.
The honest read
The point of this article — and the point of RevPerfect — is that ALOS is one of the most useful and most underused numbers on a hotel dashboard. It sits quietly between rate and profit, and it tells you something neither of those metrics knows: how the operational cost of your business is being absorbed across the room nights you sold. If your dashboard reports ALOS as a single line, alongside the other operational trivia, it is reporting it wrong. Bring it forward. Read it by segment, by arrival day, and by month. Read it next to ADR and net RevPAR. Then read it next to the housekeeping line on the cost side. Three months later, the picture will look different.
That is the gap RevPerfect was built to close — to bring the metrics that quietly determine margin out of the appendix and into the same view as the headline numbers. Try RevPerfect free → or book a 20-minute walkthrough and I'll show you what your ALOS curve has actually been doing.