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Handwritten thank you notes increase sales
Give a note thanking customers for their purchase. They must be handwritten, but photocopies work just as well as originals. In experiments, they increased future customers spending 2x.
Topics: Ecommerce | Customer Experience
For: B2C, B2B Friendly
Research date: July 2022
Universities: Robert H. Smith School of Business, University of Maryland & School of Business, Yonsei University
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š Intro
When people buy from you online, human contact is minimal.
But weāve seen before that there are many benefits to humanizing your business, such as higher sales and customer satisfaction.
Today we look at a new way to do that.
And itās incredibly easy and effective.
š Recommendation
Give customers a high-quality copy of a handwritten note to thank them for their purchase.
They will be more likely to buy from you again.
Donāt combine it with a discount or other promotions, or the positive effect disappears.

š Findings
A handwritten thank you note - or a photocopy of one - increases future customer spending.
This study focused on notes in ecommerce deliveries, but previous research suggests the effect extends to service context too (e.g. hotels, restaurants).
The positive effect:
Only works on customers with some feeling of loyalty towards the brand
Reduces or disappears if given at the same time as a free gift (e.g. a free product sample) or a discount coupon for future purchases
An experiment with a South Korean online beauty retailer tested different types of notes on 1,232 customers, then analyzed their future spending. People that received:
No note, spent $25.97
A photocopy of a handwritten note, spent $52.07 - double the amount
An original handwritten note, spent similar to those that received a photocopy
A machine-written note (in Malgun Gothic font, similar to Calibri), spent similar to those that did not receive one
Customers that received a photocopy of a handwritten note spent 100.5% more than those that received no note

š§ Why it works
Handwritten notes are a human touch that make us feel that the company is warm, caring, and sincere. So we are more likely to buy from it again.
A discount offer or a free sample are obvious incentives to get us to buy again. These contrast with the warmth of a handwritten note, so they reduce the effect.
When we feel closer (and loyal) to a brand, we appreciate warmth from them more, so a handwritten note has a much stronger effect.
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ā Limitations
Notes in this study were not personalized (they used āDear customerā). Personalizing notes with the customerās name could increase the effectiveness of handwritten notes.
Itās unclear whether and how the effect changes once customers expect a handwritten note. For example, because they received one in a previous order or they know the company always sends one to customers.
The study only tested beauty products, which are highly hedonic and emotion-related. The effect may be different for utilitarian products (e.g. a screwdriver).
The experiments used short notes (3-5 lines). Itās unclear if more detailed notes (e.g. describing the productās origins) would add to the effect or detract from it because they become too long.
Does a picture of a handwritten note shared digitally (such as the one I wrote below) have a similar effect? What about a thank you message on a website that is written in a handwritten-like font? We donāt have direct answers to these questions from this study, but they may be worth testing.
š¢ Companies using this
The vast majority of companies donāt use handwritten notes.
There are a few exceptions, mainly in the luxury and fashion world.
Audrey Leighton includes a note with a handwritten-like font when sending orders. Itās unclear if it has the same effect as a purely handwritten note. They also scent their packaging, which as weāve seen before is a smart technique.

ā” Steps to implement
Personally write a note or find someone with a nice and readable handwriting to write it.
Thank the customer for buying from you and wish them well with using your product.
Photocopy the note in high quality so that it looks and feels as if itās an original.
If your customers regularly repeat buy from you, consider writing different versions of the note and rotating them to keep things fresh.
Remember that you can also use handwritten-like fonts on your packaging, website, or ads to increase sales - if your product is hedonic.
My personal thank you note to you (pardon my handwriting)

š Study type
Online experiment and field experiment (on 1,232 customers of a South Korean online retailer between February 21 and February 28, 2017)
š Research
Do Handwritten Notes Benefit Online Retailers? A Field Experiment. Journal of Interactive Marketing (July 2022).
š« Researchers
Sanghwa Kim. Robert H. Smith School of Business, University of Maryland.
Jeonghye Choi. School of Business, Yonsei University.
Seung Hyun Kim. School of Business, Yonsei University.
Remember: This is a new scientific discovery. In the future it will probably be better understood and could even be proven wrong (thatās how science works). It may also not be generalizable to your situation. If itās a risky change, always test it on a small scale before rolling it out widely.
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