diff --git a/src/primitive.rs b/src/primitive.rs
index 623757ea..59436c46 100644
--- a/src/primitive.rs
+++ b/src/primitive.rs
@@ -1,5 +1,7 @@
 //! Implementation of the FiniteF64 primitive
 
+use core::cmp::Ordering;
+
 use crate::{TemporalError, TemporalResult};
 use num_traits::{AsPrimitive, FromPrimitive, PrimInt};
 
@@ -215,6 +217,20 @@ impl PartialOrd<f64> for FiniteF64 {
     }
 }
 
+impl Eq for FiniteF64 {}
+
+impl Ord for FiniteF64 {
+    fn cmp(&self, other: &Self) -> Ordering {
+        match self.0.partial_cmp(&other.0) {
+            Some(ordering) => ordering,
+            None => {
+                debug_assert!(false, "could not compare finite f64: {self} {other}");
+                Ordering::Equal
+            }
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::FiniteF64;