diff --git a/requirements.txt b/requirements.txt
index 349607b3..49c09e81 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -72,7 +72,7 @@ govuk-country-register==0.5.0
     # via digitalmarketplace-utils
 govuk-frontend-jinja @ git+https://github.com/Crown-Commercial-Service/govuk-frontend-jinja.git@v0.5.2-alpha
     # via -r requirements.in
-idna==2.9
+idna==3.7
     # via
     #   email-validator
     #   requests