diff --git a/crates/iceberg/public-api.txt b/crates/iceberg/public-api.txt
index eb2d4f932b..19b5592590 100644
--- a/crates/iceberg/public-api.txt
+++ b/crates/iceberg/public-api.txt
@@ -2079,7 +2079,7 @@ pub fn iceberg::spec::ManifestWriterBuilder::build_v2_deletes(self) -> iceberg::
 pub fn iceberg::spec::ManifestWriterBuilder::build_v3_data(self) -> iceberg::spec::ManifestWriter
 pub fn iceberg::spec::ManifestWriterBuilder::build_v3_deletes(self) -> iceberg::spec::ManifestWriter
 pub fn iceberg::spec::ManifestWriterBuilder::new(output: iceberg::io::OutputFile, snapshot_id: core::option::Option<i64>, key_metadata: core::option::Option<alloc::vec::Vec<u8>>, schema: iceberg::spec::SchemaRef, partition_spec: iceberg::spec::PartitionSpec) -> Self
-pub fn iceberg::spec::ManifestWriterBuilder::new_from_encrypted(encrypted_output: iceberg::encryption::EncryptedOutputFile, snapshot_id: core::option::Option<i64>, key_metadata: core::option::Option<alloc::vec::Vec<u8>>, schema: iceberg::spec::SchemaRef, partition_spec: iceberg::spec::PartitionSpec) -> Self
+pub fn iceberg::spec::ManifestWriterBuilder::new_from_encrypted(encrypted_output: iceberg::encryption::EncryptedOutputFile, snapshot_id: core::option::Option<i64>, schema: iceberg::spec::SchemaRef, partition_spec: iceberg::spec::PartitionSpec) -> iceberg::Result<Self>
 pub struct iceberg::spec::Map
 impl iceberg::spec::Map
 pub fn iceberg::spec::Map::get(&self, key: &iceberg::spec::Literal) -> core::option::Option<&core::option::Option<iceberg::spec::Literal>>
diff --git a/crates/iceberg/src/spec/manifest/writer.rs b/crates/iceberg/src/spec/manifest/writer.rs
index 88da1a396c..ae6d6e0680 100644
--- a/crates/iceberg/src/spec/manifest/writer.rs
+++ b/crates/iceberg/src/spec/manifest/writer.rs
@@ -81,19 +81,19 @@ impl ManifestWriterBuilder {
     pub fn new_from_encrypted(
         encrypted_output: EncryptedOutputFile,
         snapshot_id: Option<i64>,
-        key_metadata: Option<Vec<u8>>,
         schema: SchemaRef,
         partition_spec: PartitionSpec,
-    ) -> Self {
+    ) -> Result<Self> {
         let location = encrypted_output.location().to_owned();
-        Self {
+        let key_metadata = Some(encrypted_output.key_metadata().encode()?.to_vec());
+        Ok(Self {
             writer_future: Box::pin(async move { encrypted_output.writer().await }),
             location,
             snapshot_id,
             key_metadata,
             schema,
             partition_spec,
-        }
+        })
     }
 
     /// Build a [`ManifestWriter`] for format version 1.
@@ -124,6 +124,7 @@ impl ManifestWriterBuilder {
             .format_version(FormatVersion::V2)
             .content(ManifestContentType::Data)
             .build();
+
         ManifestWriter::new(
             self.writer_future,
             self.location,