diff --git a/.changeset/happy-brooms-lick.md b/.changeset/happy-brooms-lick.md
new file mode 100644
index 0000000000..e60aa51817
--- /dev/null
+++ b/.changeset/happy-brooms-lick.md
@@ -0,0 +1,5 @@
+---
+"@primer/css": patch
+---
+
+Add default `::selection` color
diff --git a/src/base/base.scss b/src/base/base.scss
index c12269ed19..6ee57b59b6 100644
--- a/src/base/base.scss
+++ b/src/base/base.scss
@@ -3,6 +3,10 @@
   box-sizing: border-box;
 }
 
+*::selection {
+  background-color: var(--color-accent-subtle);
+}
+
 input,
 select,
 textarea,