Loop length, slot share and how often an ad plays
An in-store screen plays a rotating sequence of content. The loop is the full sequence, the slot is one advertiser's place in it, and slot share is the proportion of the loop a brand holds. Those three determine how often an ad plays and therefore what a campaign actually delivers.
They are simple concepts and they are the mechanics underneath every impression figure quoted for the channel.
How does loop length affect delivery?
A shorter loop means each slot recurs more often, so a shopper present for a given time is more likely to see a given ad. A longer loop carries more advertisers and gives each one fewer plays per hour.
That is a direct trade between inventory and delivery, and it is decided by the network rather than by the advertiser. It is worth knowing what it is before assessing an impression estimate.
What is slot share?
The share of the loop an advertiser holds — one slot in a loop of a given length, or several. Holding multiple slots increases frequency for a shopper present for a short time, which is the common case in a convenience store.
Ask how many slots the loop contains and how many you are buying. Those two numbers determine the exposure arithmetic and they are frequently absent from a proposal.
Why does dwell time interact with this?
Because a shopper present for a short period sees only the portion of the loop that plays while they are there. If the loop is longer than the dwell, some advertisers in the loop are not seen at all by that shopper.
In a store where trips are short, loop length relative to typical dwell is the most consequential structural fact about the medium. A loop far longer than the average dwell delivers much less than its slot count suggests.
How should a brand think about frequency here?
As exposures per visit rather than per week. A shopper visiting a store several times a week in a channel where visits are frequent accumulates frequency quickly, and the per-visit figure is what the loop controls.
That is a genuine structural advantage of a daily-visit channel and it should be assessed with the loop mechanics rather than assumed.
What about competitive separation?
Whether two competing brands can appear in the same loop, and how close together, is a policy question worth asking. Networks vary and some offer category exclusivity for a period.
The answer affects the value of the buy. Appearing adjacent to a direct competitor in a short loop is a different proposition from holding the only slot in a category.
What should a proposal state?
Loop length, slot count, slots purchased, and the expected plays per hour per screen. Four figures, and their absence makes an impression estimate impossible to check.
Ask how each is measured rather than estimated. Playout logs can report plays directly, which is a considerably stronger basis than a modelled figure.
Does the loop change?
Yes, as advertisers come and go, which means delivery changes during a flight. A network that reports actual plays rather than planned ones is reporting what happened.
Frequently asked questions
Is a shorter loop always better for an advertiser?
For delivery, yes, and it also means fewer advertisers share the screen, which typically raises the price. The relevant comparison is delivered plays per pound rather than loop length alone.
How many slots should a brand buy?
Enough that a typical shopper visit contains at least one play, which is an arithmetic question given the loop and the dwell. Buying beyond that raises frequency within a visit, which has diminishing value quickly.
Can I choose my position in the loop?
Some networks offer it and most rotate. Fixed position matters less in a rotating loop than it does in a broadcast break, because there is no appointment viewing to be adjacent to.
What happens if a screen is off?
The loop does not play and the impressions do not occur, which is why uptime reporting matters as much as loop mechanics. A delivery figure that assumes uptime is an estimate rather than a count.
Does the loop include store content?
Frequently, and store or network content in the loop reduces advertiser slots. Ask what proportion of the loop is commercial inventory.
How does this compare to programmatic digital out-of-home?
The same mechanics apply, with slots allocated dynamically rather than fixed. Programmatic buying changes how the slot is transacted and not how the loop physically works.
What is a reasonable loop length?
There is no universal figure and it should be assessed against the store's typical dwell. A loop that exceeds the time a shopper spends in front of the screen is delivering less than its slot count implies.
Should loop length appear in reporting?
It should be stated in the plan, and delivery should be reported as actual plays. Between those two a buyer can check whether the campaign ran as sold.
What is the first question to ask a network?
How long is the loop and how many commercial slots does it contain. Everything about delivery follows from those two numbers.
### What should be checked after the flight?
Actual plays per screen per day against the plan, from playout logs. That single comparison verifies the loop mechanics delivered what the proposal described.
Discrepancies usually have an explanation — added advertisers, downtime, a schedule change — and the explanation is worth having. A flight where delivered plays materially undershot the plan is a make-good conversation rather than a reporting footnote.
Does the loop change between stores?
It can, where different stores run different content or different local inventory. Ask whether the loop is uniform across the estate, because a national average loop length can conceal substantial variation.
### How does loop composition affect the buy?
Who else is in the loop matters as much as how many. A loop shared with adjacent categories is a different environment from one shared with unrelated ones, and adjacency policy is what governs it.
Ask what proportion of the loop is national advertising, local advertising and store content. That composition describes the environment a shopper actually sees.
Is a guaranteed play count available?
Some networks offer one and it shifts the delivery risk appropriately. Where it is available it is usually a better basis than a share of an unspecified loop.
Considering NRS Digital Media? Start at nrsdigitalmedia.com, read the media deck, or contact the team.