The island booth price premium and what four open sides are really worth

Somebody in finance pulls the contract file, groups it by booth type, and comes back with a slide saying that island space realised 31.20 per square foot last edition while inline space realised 33.80. The island booth price premium on the card is 20 per cent. The slide concludes that islands are underpriced by about 8 per cent and recommends a correction.

The slide is arithmetically correct and the recommendation is wrong, and the reason is worth understanding before anyone touches the card, because the same mistake is available on every floor with a size ladder on it.

Why does the first comparison always come out backwards?

Islands are large. Your size ladder, if you have one, charges less per square foot as booths get bigger. So the average island is being priced off a lower rung before any location premium is applied, and the blended rate you observe is the ladder and the premium tangled together, with the ladder usually winning.

Put a ladder on it: 30 dollars per square foot to 400 square feet, 27.50 above that, applied marginally. A 400 square foot island carries a card rate of 30.00. A 900 square foot island is 400 at 30 plus 500 at 27.50, which is 12,000 plus 13,750, or 25,750, and 25,750 over 900 square feet is a card rate of 28.61 before location.

Now compute, for every contracted booth, the rate the published card implies for a booth of that size, ignoring location. Divide the paid rate by that number and you have a realisation ratio: what the account paid relative to what size alone says it should have paid.

On the file above, say the islands average a card rate of 27.90 and paid 31.20, so the ratio is 1.118. The inline stock averages a card rate of 30.00 and paid 33.80, a ratio of 1.127.

Islands carry an 11.8 per cent premium over card and inline carries 12.7 per cent, and the 20 per cent on your rate card describes neither. What you have measured is that your corner adder and zone adjustments on inline space are doing at least as much work as your island premium, which is a different finding from the one on the slide and considerably more useful.

The comparison that isolates the thing you want

Averages across a whole floor cannot separate size from location, because on your floor the two are correlated by construction. Match instead.

Find every island of one size band in one zone, and every inline block of the same size in the same zone, in the same edition. Fitting a location model is the other route, and it wants three editions rather than one. Those booths differ in open sides and in almost nothing else.

Take 400 square feet as the band, because most floors have both a 20 by 20 island and a 10 by 40 inline run at that size. Say the premium zone contains 18 islands of 400 square feet with a mean paid rate of 35.60, and 11 inline blocks of 400 square feet with a mean paid rate of 30.90.

The difference is 4.70 per square foot, which against 30.90 is 15.2 per cent. That is your island premium, measured on your own floor with the ladder and the zone held fixed.

Check whether the number can carry any weight before you use it. If the island rates have a standard deviation of 3.10 across 18 contracts, the standard error is 3.10 over the square root of 18, or 0.73. If the inline rates have a standard deviation of 2.40 across 11, the standard error is 0.72. The standard error of the difference is the square root of 0.73 squared plus 0.72 squared, which is 1.03. A gap of 4.70 against a standard error of 1.03 is about 4.6 standard errors, which is a real difference rather than an artefact of who happened to sign.

Run the same calculation on your 900 square foot band and your 1,600 square foot band. If the premium is stable across bands, express it as a percentage. If it falls as booths get larger, which is common, the premium belongs on the card as a banded figure rather than a single multiplier.

What the 20 per cent on the card is actually collecting

The gap between the card premium and the measured premium is money, and it is easy to size.

Forty islands of 400 square feet is 16,000 square feet. At a 30 dollar base that is 480,000 dollars of space before location. A 20 per cent island uplift on that is 96,000 dollars.

At the measured 15.2 per cent it is 72,960. The difference, 23,040 dollars, is the part of your published premium that never survived the sales cycle. It went out in negotiations, in matched-rate concessions to accounts that moved from inline, and in the quiet rounding that happens when a seller has to justify a five-figure line item.

That number is worth putting in front of the sales director as a decision to be taken. Producing it is half a day of exhibitor analytics against the contract file. Either the card comes down to 15 per cent and everyone quotes a rate they can hold, or the card stays at 20 and the gap becomes a tracked exception instead of an unrecorded one.

What do four open sides give the exhibitor?

The premium is easier to defend once you can say what it buys, and the build rules say it precisely.

Under the IAEE Guidelines for Display Rules and Regulations, in the 2019 North American update, an island booth is typically 20 by 20 feet or larger and the entire cubic content of the space may be used, up to a maximum height normally set between 16 and 20 feet including signage. A linear booth in the same hall is held to an 8 foot back wall with materials within 5 feet of the aisle restricted to 4 feet.

An island exhibitor can therefore build upward, hang a sign that is visible across the hall, and design an approach from any direction. An inline exhibitor at four times the frontage cannot do any of that. The premium is priced against build rights and sightlines that your guidelines grant, which makes it defensible in a way that a vague appeal to traffic never is.

It also sets a limit on the premium. If your venue caps hanging signs lower than the guideline range, or your ceiling grid will not take rigging in half the hall, then islands in that half are a materially weaker product and pricing them identically is a claim you cannot support.

Reading demand without running a price experiment

You cannot run a controlled test on a floorplan. You can read the order in which stock cleared, which is the closest thing to demand evidence a sold floor produces.

Take the last three editions and record, for every island position, the date it was committed. Compute the share of island square feet sold at each of 180, 120, 90 and 60 days out, and do the same for inline. If islands are consistently gone earlier and the gap is widening across editions, the premium is under the market. If islands clear at the same pace as inline, a 20 per cent premium is a bet with nothing behind it.

UFI's 36th Global Exhibition Barometer, published in January 2026 from a survey of 378 companies across 57 countries concluded that December, found 47 per cent of respondents reporting that space rented in their own market grew by more than 5 per cent in 2025, with 44 per cent expecting the same again in 2026. That is a market-level reading, and the show-level version of it is your own clearing curve rather than the headline.

Unfilled demand for islands sits on the waitlist, which has its own treatment.

Where this stops

The matched comparison assumes that a 400 square foot island and a 400 square foot inline block in the same zone are bought by comparable accounts, and they are not. Islands are bought by exhibitors with bigger budgets, longer tenure and more at stake, which means part of the 15.2 per cent is a measurement of who buys islands rather than what an island is worth. No amount of matching inside a contract file separates those, because the assignment was never random.

The second limit is sample size. Most floors have fewer than twenty islands in any single size band, and a couple of unusual contracts move the mean noticeably. Pooling three editions helps and introduces its own problem, since rates and the mix both moved across those years. Compute the premium separately per edition first and pool only if the three numbers are close.

The third is that paid rate is not list rate. Every discount, every multi-edition deal and every sponsorship bundle that quietly included space is sitting inside the number you just computed, and islands attract more of all three than inline space does. A measured premium of 15.2 per cent might be a 20 per cent premium with a 4 per cent discount culture attached, and the fix for that is in the discounting policy rather than the card.

Pull last edition's contract file, filter to booths between 380 and 420 square feet, and split them by open sides. If you have at least eight on each side, compute the two mean paid rates and subtract. That single number is a better basis for next year's island premium than anything on the current card.