What cross category shopping reveals about loyalty members
The short answer
Average categories bought per customer is the simplest measure of cross category shopping. Count the distinct categories each customer bought from in a year, then compare loyalty members with non-members who spend a similar amount. If members still buy across more categories at the same spend level, the program is widening baskets on top of attracting bigger spenders.
Why it matters
Each category a customer adds gives them another reason to come back. Knowing whether members broaden their shopping tells you if the program builds habit across the range or simply rewards customers who would have shopped widely anyway.
The question to ask
Copy this into Lexi as written.
What the answer looks like
Illustrative output on sample data
Illustrative example: how Lexi answers this for a home improvement retailer. It counts categories bought per customer for 90,000 members and 140,000 non-members, within matching spend bands.
- Overall: members buy from 4.6 categories a year, non-members from 2.1.
- $500 to $1,000 spend band: members 3.8 categories, non-members 2.9.
What the data shows
Most of the raw gap comes from members spending more. Within the same spend band, members still buy from almost one extra category.
What it means
Members who joined through a spring promotion added garden. Members who joined at the paint counter barely broadened at all. The program widens baskets when the joining offer introduces a new category.
What to do
Tie the first member reward to a category the customer has not bought yet.
Want me to show which second category each joining source leads to?
Frequently asked questions
What counts as cross category shopping?
Cross category shopping means a customer buys from more than one product category within a period, such as a year. Define categories at a level customers recognize, like paint, garden and tools, since very fine categories inflate the counts and very broad ones hide real behavior.
Why compare members and non-members at the same spend level?
Members usually spend more, and bigger spenders naturally buy across more categories. Without matching on spend, the program gets credit for differences that come from who joins. Comparing within spend bands isolates the extra breadth that membership plausibly adds.
Which cross selling strategies suit loyalty programs?
Rewards that point to a new category are the most direct lever, such as bonus points on a first garden purchase for a member who only buys paint. Personalized category suggestions in member emails and store associate prompts at checkout add to it. Measure each against a holdout, since members who were going to broaden anyway can flatter a tactic.