diff --git a/requirements.in b/requirements.in
index 3ab578270..78d3bfae9 100644
--- a/requirements.in
+++ b/requirements.in
@@ -3,7 +3,7 @@
 
 ago==0.0.93
 govuk-bank-holidays==0.11
-humanize==3.12.0
+humanize==4.0.0
 Flask==1.1.2  # pyup: <2
 Flask-WTF==1.0.0
 wtforms==3.0.0
diff --git a/requirements.txt b/requirements.txt
index fd40d8c45..eff211618 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -83,7 +83,7 @@ greenlet==1.1.0
     # via eventlet
 gunicorn==20.1.0
     # via -r requirements.in
-humanize==3.12.0
+humanize==4.0.0
     # via -r requirements.in
 idna==2.10
     # via requests