Don't ask for reviews on weekends

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📝 Context

Topics: Reviews
For: B2C. Can be tested for B2B
Research date: October 2025
Universities: Erasmus University Rotterdam, ESADE, Reichman University, University of Mannheim

You want to get more reviews and, hopefully, that 0.5 extra star rating you’ve been working so hard for. You decide to send a reminder email to all customers who bought in the last month. 

Sending that email on a Sunday evening sounds like a great idea, most people will be relaxing at home, and may be more likely to leave a review. 

Definitely better than sending it on a Tuesday at 3pm when most people are busy at work. Right?

Unfortunately, the science says you’re wrong. Best you send it on a weekday. Here’s why.

P.S.: Make sure the first review you display is always positive. A negative first review triggers a chain reaction leading to more negative reviews.

📈 Recommendation

Send review requests on weekdays, not weekends or public holidays. 

This is particularly important if your business is crowded during weekends (e.g. restaurant, bar), or if you’re asking reviews from your employees (e.g. to review you on Glassdoor or Indeed).

People will be less likely to leave negative reviews.  

🎓 Findings

• People leave more negative reviews during weekends (vs weekdays).

• Scientists analyzed almost 400 million reviews across 33 major platforms (e.g. Amazon, Glassdoor, Yelp, and IMDb) and found that, when given on weekends (vs weekdays):

  • Star reviews were .04 stars lower on average

  • Net Promoter Scores (e.g. How likely are you to recommend to a friend?) were 3.6 points lower.  Share of positive promoter reviews (would recommend) were  3% lower and negative detractor reviews (would not recommend) were  5.7% higher

  • Up to 6% of products on Amazon with only 3 or 4 reviews  would experience a half-star increase in their average rating if weekend reviewers were excluded.

• The effect is:

  • The same worldwide (e.g. applies the same way in Iran on their weekend days of Friday and Saturday)

  • Similar for public holidays (e.g. May 1st, July 4th) on weekdays

  • Stronger on platforms where only verified reviews are accepted

  • Stronger for businesses that get more crowded during the weekend (e.g. restaurants, bars)

  • Stronger on platforms collecting employers' reviews

🧠 Why it works

• People writing reviews on weekends have fewer online and real-life friends.

• They also consistently use fewer words related to sociality (e.g. don’t mention friends, social interactions) in their reviews.

• This group of less socially connected people are more likely to write a review on a weekend and those reviews are more negative. 

• Moreover, customer service quality drops as places get more crowded during weekends.

• This makes businesses popular on weekends even more at risk of negative reviews.

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✋ Limitations

• There may also be other reasons behind the effect. For example, people may feel worse on a Sunday evening right before going back into the work week (known as “Sunday neurosis”), which could make them more likely to give a negative review.

👀 Real-life example

Booking. com sends reminder emails for reviews on weekends.

❌ Issue: The weekend timing increases the risk of negative reviews for hotels listed on Booking.com.

✅ Solution: There are a few things Booking.com could do to make people more likely to leave positive reviews:

• Stop sending them on weekends and time the emails to weekdays.

• Give incentives to people who leave reviews (e.g. a future discount, loyalty points). It increases review positivity by up to 83.4%.

• Include other people’s reviews in their reminder email, and show a 5-star first review to nudge people towards more positive reviews.

🔍 Study type

Online experiments, market observation (analysis of nearly 400 million reviews from more than 60 million users across 33 major platforms), and field experiment (reviews reminder sent by email to 11,667 users on either Wednesday or Saturday)

📖 Research

The Weekend Effect in Online Reviews. Journal of Marketing Research (October 2025)

🏫 Researchers

• Andreas Bayerl, Erasmus School of Economics, Erasmus University Rotterdam

• Verena Schoenmueller, ESADE

• Jacob Goldenberg, Reichman University

• Florian Stahl, University of Mannheim

Remember: This is a new scientific discovery. In the future it will probably be better understood and could even be proven wrong (that’s how science works). It may also not be generalizable to your situation. If it’s a risky change, always test it on a small scale before rolling it out widely.

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🎓 It took 3 of us 12 hours to accurately turn this 23-page research paper into this 3min insight. 

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