diff --git a/lib/src/component/error.rs b/lib/src/component/error.rs
index b1b47a06..dd6e3263 100644
--- a/lib/src/component/error.rs
+++ b/lib/src/component/error.rs
@@ -175,6 +175,7 @@ impl From<error::Error> for types::Error {
             Error::DictionaryError(e) => e.into(),
             Error::ObjectStoreError(e) => e.into(),
             Error::SecretStoreError(e) => e.into(),
+            Error::InvalidBackendUrl => types::Error::HttpInvalid,
             // All other hostcall errors map to a generic `ERROR` value.
             Error::AbiVersionMismatch
             | Error::BackendUrl(_)
diff --git a/lib/src/error.rs b/lib/src/error.rs
index ad0b49c7..6237734b 100644
--- a/lib/src/error.rs
+++ b/lib/src/error.rs
@@ -119,6 +119,9 @@ pub enum Error {
     #[error(transparent)]
     HttpError(#[from] http::Error),
 
+    #[error("Invalid Url")]
+    InvalidBackendUrl,
+
     #[error("Object Store '{0}' does not exist")]
     UnknownObjectStore(String),
 
@@ -184,6 +187,7 @@ impl Error {
             Error::ObjectStoreError(e) => e.into(),
             Error::SecretStoreError(e) => e.into(),
             Error::Again => FastlyStatus::Again,
+            Error::InvalidBackendUrl => FastlyStatus::Httpinvalid,
             // All other hostcall errors map to a generic `ERROR` value.
             Error::AbiVersionMismatch
             | Error::BackendUrl(_)
diff --git a/lib/src/wiggle_abi/req_impl.rs b/lib/src/wiggle_abi/req_impl.rs
index 8bd837a4..db7259f4 100644
--- a/lib/src/wiggle_abi/req_impl.rs
+++ b/lib/src/wiggle_abi/req_impl.rs
@@ -411,12 +411,18 @@ impl FastlyHttpReq for Session {
 
         let grpc = backend_info_mask.contains(BackendConfigOptions::GRPC);
 
+        let uri = match Uri::builder()
+            .scheme(scheme)
+            .authority(origin_name)
+            .path_and_query("/")
+            .build()
+        {
+            Ok(uri) => uri,
+            Err(_) => return Err(Error::InvalidBackendUrl),
+        };
+
         let new_backend = Backend {
-            uri: Uri::builder()
-                .scheme(scheme)
-                .authority(origin_name)
-                .path_and_query("/")
-                .build()?,
+            uri: uri,
             override_host,
             cert_host,
             use_sni,