Custom labels in Google Shopping: segment by margin, season and sales

Shopping campaigns give you little control over matching, so the control you do have — how the catalog is divided into groups you can bid on — matters disproportionately. Custom labels are that control. Five fields, custom_label_0 to custom_label_4, invisible to shoppers, entirely yours to define.

Most accounts either ignore them or fill them with something arbitrary once and never revisit it. Here is how to use them deliberately.

The rule that makes labels work

One label, one dimension, forever. Decide that custom_label_0 means margin band and it must always mean margin band. Campaigns, bidding rules and reports are built on these values; redefining a label silently changes what every one of them is doing.

Write the scheme down somewhere your future self and your agency will find it.

Five schemes worth using

custom_label_0 — margin band

The single most useful segmentation, because it turns "return on ad spend" into something you can act on.

Bid more where the margin absorbs it. If cost data is not in the shop, a proxy — price band, or brand-owned versus resale — is still better than nothing.

custom_label_1 — stock cover

Advertising a product you are about to run out of wastes money; so does ignoring the stock you must clear.

custom_label_2 — price band

Useful because shopper behaviour and competition differ sharply by price: under-25, 25-75, 75-200, over-200. Bands also make reports readable at a glance.

custom_label_3 — season or collection

spring-summer-2026, winter, all-year, christmas. Seasonal products need budget before the season, not during it, and a label is how you pull that lever early.

custom_label_4 — performance

The one that should be recalculated from data rather than typed: bestseller, steady, slow, never-sold.

Filling the performance label from GA4

"Best-seller" is a fact, not an opinion, and it changes every month. If your feed tool can read Google Analytics 4, the label can be derived instead of maintained.

The logic is simple:

• purchases in the last 30 days ≥ 20 → bestseller
• purchases ≥ 5 → steady
• purchases ≥ 1 → slow
• otherwise, and if the product has had more than 200 views → never-sold

That last group is the interesting one: products people look at and do not buy. Usually the price, the images or the description is the problem, and the label makes them easy to pull out and look at.

In FeedManager this is a connection and a rule. Connect Google Analytics 4 with Sign in with Google, pick the property, choose which field matches products (the item id, SKU, item group or GTIN), and the per-product numbers — views, list clicks, add-to-carts, purchases and revenue for the last 7, 30 or 90 days — become available to rules like any other field. The rule then writes custom_label_4, and every rebuild recalculates it.

Using the labels once they exist

Campaign structure. Split campaigns or ad groups by custom_label_0 so high-margin products can carry a higher target. Give clearance its own campaign with a deliberately generous bid until the stock is gone.

Negative segmentation. Put no-margin and never-sold into a campaign you pause, or filter them out of the feed entirely. There is no reason to pay for clicks on products you do not want to sell.

Seasonal timing. Two weeks before the season, raise budgets on the season label. Afterwards, move the same products to clearance.

Reporting. The fastest way to explain Shopping performance to a finance team is a table by margin band and price band. Both come free once the labels exist.

Keeping the values honest

• Recalculate on a schedule. Margin and stock change daily; performance changes weekly. Labels derived from those numbers should be rebuilt with the feed, not updated by hand.
• Use few values. Four or five per label. Fifteen values produce groups too small to bid on.
• Never leave a label empty. Every product should have a value, even if it is unknown — otherwise campaign filters silently skip it.
• Do not encode two things in one label. high-margin-winter is a trap: you cannot filter on either part.
• Watch for value drift. If a label's distribution shifts suddenly, the data behind it changed, not the catalog.

Labels are the cheapest structure you can add to a Shopping account: no new creative, no new budget, and they turn one undifferentiated catalog into segments you can actually manage. The work is not in the ads — it is in making the feed carry the numbers you already have.

Frequently asked questions