diff --git a/tokio/Cargo.toml b/tokio/Cargo.toml
index 5f347d043..e76323bf1 100644
--- a/tokio/Cargo.toml
+++ b/tokio/Cargo.toml
@@ -68,7 +68,7 @@ process = [
   "winapi/threadpoollegacyapiset",
 ]
 # Includes basic task execution capabilities
-rt = ["slab"]
+rt = []
 rt-multi-thread = [
   "num_cpus",
   "rt",
@@ -98,7 +98,6 @@ memchr = { version = "2.2", optional = true }
 mio = { version = "0.7.6", optional = true }
 num_cpus = { version = "1.8.0", optional = true }
 parking_lot = { version = "0.11.0", optional = true }
-slab = { version = "0.4.1", optional = true }
 
 # Currently unstable. The API exposed by these features may be broken at any time.
 # Requires `--cfg tokio_unstable` to enable.