Costco and Aldi take different approaches to value in the U.S. grocery market, with Costco's membership-based warehouse model contrasting with Aldi's discount supermarket format. Both, however, compete for shoppers looking to get more for their money.
So, how do the two brands compare in terms of value for money perception?
YouGov BrandIndex data reveals how consumer attitudes shift across each generation of grocery shoppers – with a deep dive look at value perception among Gen Z consumers.
Costco vs. Aldi: Value perception by generation
While Costco wins the overall value crown with a net score of 38 among U.S. adults (compared to Aldi’s score of 35), perception shifts significantly based on generation.
Gen Z records the greatest gap between the two budget-focused brands. Between January and August 2026, Costco recorded a Value score of 44 among Gen Z adults, compared with 32 for Aldi – a 12-point difference in net score.
The gap is smaller among Millennials, at nine points (43 vs. 34), while the picture reverses among Gen X, with Aldi scoring 35 compared with Costco's 33. Among Baby Boomers+, the two brands are tied on 37.
But the overall Gen Z scores mask considerable movement over the course of the year. A closer look at the two brands' Value scores since January reveals how their positions among Gen Z have shifted during 2026.
Tracking perception among Gen Z in 2026
Gen Z is an important part of both retailers' customer bases. According to YouGov Profiles, adult Gen Z Americans make up 18% of Costco's current customers and 13% of Aldi's.
While the year-to-date stats show Costco holding a clear value perception lead among Gen Z, YouGov BrandIndex over time analysis shows a more competitive battle. Costco entered 2026 with a substantial value perception lead among Gen Z adults in the U.S., posting a score of 46 on January 1 compared with Aldi's 27.
Despite a clear lead, the gap between the two brands has fluctuated throughout the year. Aldi's Value score climbed through January, reaching a year-to-date high of 41 on January 29. By the end of the month, Costco's lead had narrowed to nine points, with a Value score of 49 compared with Aldi's 40.
Costco's score strengthened again heading into the summer, reaching 51 on June 7, compared with Aldi's 33. By the end of June, Costco held a 13-point lead, scoring 48 against Aldi's 34.
That advantage narrowed over the following two months, driven largely by a decline in Costco's Value score. Costco fell from 48 at the end of June to 40 at the end of July and 38 by August 31. Aldi's score changed less over the same period, moving from 34 at the end of June to 32 at the end of July and 33 at the end of August.
As things stand, the two brands are much closer on Gen Z value perceptions than they were at the beginning of the year. Costco has recorded a consistent period of decline since mid-June, while Aldi is gradually tracking upwards. As holiday season approaches, could Gen Z’s value crown be in line for a new monarch?
Methodology:
YouGov BrandIndex collects data on thousands of brands every day. Costco and Aldi’s Value scores are based on the questions: Which of the following brands do you think represents GOOD VALUE FOR MONEY? By that we don't mean "cheap," but that the brands offer a customer a lot in return for the price paid. / Now which of the following brands do you think represents POOR VALUE FOR MONEY? By that, we don't mean "expensive," but that the brands do not offer a customer much in return for the price paid.
Scores are reported as net scores from –100 to +100, based on daily surveys of US adults. Data is weighted using a propensity scoring methodology with targets from the American Community Survey (ACS) to ensure representation by age, gender, race, education, and region. Figures are shown as an 8-week moving average between January 1 – August 31, 2026.
YouGov Profiles is based on continuously collected data through rolling surveys, rather than a single limited questionnaire. Figures are drawn from responses collected between September 2025 and September 2026, using a 52-week dataset updated weekly. Data is nationally representative of adults (18+) in the US and weighted by age, gender, education, region, and race.
Image credits: Getty Images
