diff --git a/.changeset/update_gosiatechcoreutils_to_v0216.md b/.changeset/update_gosiatechcoreutils_to_v0216.md
new file mode 100644
index 00000000..ee197583
--- /dev/null
+++ b/.changeset/update_gosiatechcoreutils_to_v0216.md
@@ -0,0 +1,5 @@
+---
+default: patch
+---
+
+# Update go.sia.tech/coreutils to v0.21.6.
diff --git a/go.mod b/go.mod
index 9cf00910..0a08252f 100644
--- a/go.mod
+++ b/go.mod
@@ -6,7 +6,7 @@ require (
 	github.com/quic-go/quic-go v0.60.0
 	github.com/quic-go/webtransport-go v0.11.1
 	go.etcd.io/bbolt v1.5.0
-	go.sia.tech/core v0.21.5
+	go.sia.tech/core v0.21.6
 	go.sia.tech/mux v1.5.2
 	go.uber.org/zap v1.28.0
 	golang.org/x/crypto v0.53.0
diff --git a/go.sum b/go.sum
index 0b803c20..bc55468a 100644
--- a/go.sum
+++ b/go.sum
@@ -16,8 +16,8 @@ github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
 go.etcd.io/bbolt v1.5.0 h1:S7GAl7Fxv12yohbwFfIbQCGDWbQbtDGPET4P/bD4lxU=
 go.etcd.io/bbolt v1.5.0/go.mod h1:mkltfYE5aUHQxUct9N9V+Kp7aSjFqjgrhcXIS70Lrdk=
-go.sia.tech/core v0.21.5 h1:tIGizUDbezS2VhsX9U+aJGaU0iKlCMdDjP8FRGPNRls=
-go.sia.tech/core v0.21.5/go.mod h1:AluTCM6Q+1YAw9nXNz2un4NEh4J8GPySEuYxBdCvlCM=
+go.sia.tech/core v0.21.6 h1:fge57Itz8R9jXegVd63y/jIQHAOLS+X2mEqYnbw1d/k=
+go.sia.tech/core v0.21.6/go.mod h1:UAc637UMThRXG13B2SEc9MCmJSsh7yuF78VfvweXyhE=
 go.sia.tech/mux v1.5.2 h1:MU07hUSZJJNo+ulN/7Gb5/3KBLaxXgunb63fIhxFy+o=
 go.sia.tech/mux v1.5.2/go.mod h1:MW00TmBIJY4CrdOwKohBaGalbBf27/Zcf2S5YVIEMn8=
 go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=