diff --git a/.github/workflows/oldest-test-reqs.txt b/.github/workflows/oldest-test-reqs.txt
index afdbcb13e..d7b8c60b4 100644
--- a/.github/workflows/oldest-test-reqs.txt
+++ b/.github/workflows/oldest-test-reqs.txt
@@ -4,7 +4,7 @@ cython==3.0.2
 dynasor==1.1b0; platform_system != "Windows"
 gsd==2.4.2
 matplotlib==3.2.0
-numpy==1.15.0
+numpy==1.18.0
 pillow==7.0.0
 pytest==6.2.2
 rowan==1.2.1