diff --git a/Cargo.lock b/Cargo.lock
index da71c422e..ebb406c65 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2537,9 +2537,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.15.0"
+version = "1.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e82dad04139b71a90c080c8463fe0dc7902db5192d939bd0950f074d014339e1"
+checksum = "86f0b0d4bf799edbc74508c1e8bf170ff5f41238e5f8225603ca7caaae2b7860"
 
 [[package]]
 name = "oorandom"
diff --git a/zebra-consensus/Cargo.toml b/zebra-consensus/Cargo.toml
index 7e1769a64..520d7b78c 100644
--- a/zebra-consensus/Cargo.toml
+++ b/zebra-consensus/Cargo.toml
@@ -22,7 +22,7 @@ chrono = { version = "0.4.22", default-features = false, features = ["clock", "s
 dirs = "4.0.0"
 displaydoc = "0.2.3"
 lazy_static = "1.4.0"
-once_cell = "1.15.0"
+once_cell = "1.16.0"
 serde = { version = "1.0.147", features = ["serde_derive"] }
 
 futures = "0.3.25"
diff --git a/zebra-state/Cargo.toml b/zebra-state/Cargo.toml
index a3565b4bd..cb1f8f7d5 100644
--- a/zebra-state/Cargo.toml
+++ b/zebra-state/Cargo.toml
@@ -45,7 +45,7 @@ color-eyre = "0.6.2"
 # Enable a feature that makes tinyvec compile much faster.
 tinyvec = { version = "1.6.0", features = ["rustc_1_55"] }
 
-once_cell = "1.15.0"
+once_cell = "1.16.0"
 spandoc = "0.2.2"
 
 hex = { version = "0.4.3", features = ["serde"] }
diff --git a/zebra-test/Cargo.toml b/zebra-test/Cargo.toml
index 81a491fd6..ad783ba25 100644
--- a/zebra-test/Cargo.toml
+++ b/zebra-test/Cargo.toml
@@ -13,7 +13,7 @@ indexmap = "1.9.1"
 lazy_static = "1.4.0"
 insta = "1.21.0"
 proptest = "0.10.1"
-once_cell = "1.15.0"
+once_cell = "1.16.0"
 rand = { version = "0.8.5", package = "rand" }
 regex = "1.6.0"
 
diff --git a/zebrad/Cargo.toml b/zebrad/Cargo.toml
index 75126552e..0d6660482 100644
--- a/zebrad/Cargo.toml
+++ b/zebrad/Cargo.toml
@@ -152,7 +152,7 @@ tonic-build = { version = "0.8.0", optional = true }
 [dev-dependencies]
 abscissa_core = { version = "0.5", features = ["testing"] }
 hex = "0.4.3"
-once_cell = "1.15.0"
+once_cell = "1.16.0"
 regex = "1.6.0"
 semver = "1.0.14"