diff --git a/Package.resolved b/Package.resolved
index 01491b1cf6cb..f3c2f92af558 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -50,8 +50,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-collections",
       "state" : {
-        "revision" : "a902f1823a7ff3c9ab2fba0f992396b948eda307",
-        "version" : "1.0.5"
+        "revision" : "94cf62b3ba8d4bed62680a282d4c25f9c63c2efb",
+        "version" : "1.1.0"
       }
     },
     {
diff --git a/Package.swift b/Package.swift
index f0585cce0218..c3fb043097b3 100644
--- a/Package.swift
+++ b/Package.swift
@@ -17,7 +17,7 @@ let package = Package(
     )
   ],
   dependencies: [
-    .package(url: "https://github.com/apple/swift-collections", from: "1.0.2"),
+    .package(url: "https://github.com/apple/swift-collections", from: "1.1.0"),
     .package(url: "https://github.com/apple/swift-docc-plugin", from: "1.0.0"),
     .package(url: "https://github.com/google/swift-benchmark", from: "0.1.0"),
     .package(url: "https://github.com/pointfreeco/combine-schedulers", from: "1.0.0"),
diff --git a/Package@swift-5.9.swift b/Package@swift-5.9.swift
index bdf6394bed7b..9e89e0fe76c6 100644
--- a/Package@swift-5.9.swift
+++ b/Package@swift-5.9.swift
@@ -18,7 +18,7 @@ let package = Package(
     )
   ],
   dependencies: [
-    .package(url: "https://github.com/apple/swift-collections", from: "1.0.2"),
+    .package(url: "https://github.com/apple/swift-collections", from: "1.1.0"),
     .package(url: "https://github.com/apple/swift-docc-plugin", from: "1.0.0"),
     .package(url: "https://github.com/apple/swift-syntax", "509.0.0"..<"511.0.0"),
     .package(url: "https://github.com/google/swift-benchmark", from: "0.1.0"),
diff --git a/Sources/ComposableArchitecture/Reducer/Reducers/StackReducer.swift b/Sources/ComposableArchitecture/Reducer/Reducers/StackReducer.swift
index e179f53ebcf8..a7f04028759b 100644
--- a/Sources/ComposableArchitecture/Reducer/Reducers/StackReducer.swift
+++ b/Sources/ComposableArchitecture/Reducer/Reducers/StackReducer.swift
@@ -183,8 +183,7 @@ extension StackState: Hashable where Element: Hashable {
   }
 }
 
-// NB: We can remove `@unchecked` when swift-collections 1.1 is released.
-extension StackState: @unchecked Sendable where Element: Sendable {}
+extension StackState: Sendable where Element: Sendable {}
 
 extension StackState: Decodable where Element: Decodable {
   public init(from decoder: Decoder) throws {