diff --git a/rtic-monotonics/CHANGELOG.md b/rtic-monotonics/CHANGELOG.md
index d3a9d846ee..1ccf28a5d0 100644
--- a/rtic-monotonics/CHANGELOG.md
+++ b/rtic-monotonics/CHANGELOG.md
@@ -13,4 +13,6 @@ For each category, *Added*, *Changed*, *Fixed* add new entries at the top!
 
 ### Fixed
 
+- Unmask the `rp2040` interrupt
+
 ## [v1.0.0] - 2023-xx-xx
diff --git a/rtic-monotonics/src/rp2040.rs b/rtic-monotonics/src/rp2040.rs
index e42c148e4c..6599dc6a7e 100644
--- a/rtic-monotonics/src/rp2040.rs
+++ b/rtic-monotonics/src/rp2040.rs
@@ -4,7 +4,7 @@ use super::Monotonic;
 pub use super::{TimeoutError, TimerQueue};
 use core::future::Future;
 pub use fugit::ExtU64;
-use rp2040_pac::{timer, Interrupt, RESETS, TIMER};
+use rp2040_pac::{timer, Interrupt, NVIC, RESETS, TIMER};
 
 /// Timer implementing `rtic_monotonic::Monotonic` which runs at 1 MHz.
 pub struct Timer;
@@ -17,6 +17,8 @@ impl Timer {
         timer.inte.modify(|_, w| w.alarm_0().set_bit());
 
         TIMER_QUEUE.initialize(Self {});
+
+        unsafe { NVIC::unmask(Interrupt::TIMER_IRQ_0) };
     }
 
     fn timer() -> &'static timer::RegisterBlock {