diff --git a/qiskit_ibm/api/clients/runtime.py b/qiskit_ibm/api/clients/runtime.py
index 9844f2b76..01ff6aff2 100644
--- a/qiskit_ibm/api/clients/runtime.py
+++ b/qiskit_ibm/api/clients/runtime.py
@@ -117,7 +117,7 @@ def program_run(
             program_id: str,
             credentials: Credentials,
             backend_name: str,
-            params: str,
+            params: Dict,
             image: str
     ) -> Dict:
         """Run the specified program.
diff --git a/qiskit_ibm/api/rest/runtime.py b/qiskit_ibm/api/rest/runtime.py
index 01626efee..48cfde212 100644
--- a/qiskit_ibm/api/rest/runtime.py
+++ b/qiskit_ibm/api/rest/runtime.py
@@ -19,6 +19,7 @@
 
 from .base import RestAdapterBase
 from ..session import RetrySession
+from ...runtime.utils import RuntimeEncoder
 
 logger = logging.getLogger(__name__)
 
@@ -104,7 +105,7 @@ def program_run(
             group: str,
             project: str,
             backend_name: str,
-            params: str,
+            params: Dict,
             image: str
     ) -> Dict:
         """Execute the program.
@@ -131,7 +132,7 @@ def program_run(
             'params': [params],
             'runtime': image
         }
-        data = json.dumps(payload)
+        data = json.dumps(payload, cls=RuntimeEncoder)
         return self.session.post(url, data=data).json()
 
     def jobs_get(self, limit: int = None, skip: int = None, pending: bool = None) -> Dict:
diff --git a/qiskit_ibm/runtime/ibm_runtime_service.py b/qiskit_ibm/runtime/ibm_runtime_service.py
index a680afd49..374fd8020 100644
--- a/qiskit_ibm/runtime/ibm_runtime_service.py
+++ b/qiskit_ibm/runtime/ibm_runtime_service.py
@@ -22,7 +22,7 @@
 
 from .runtime_job import RuntimeJob
 from .runtime_program import RuntimeProgram, ParameterNamespace
-from .utils import RuntimeEncoder, RuntimeDecoder, to_base64_string
+from .utils import RuntimeDecoder, to_base64_string
 from .exceptions import (QiskitRuntimeError, RuntimeDuplicateProgramError, RuntimeProgramNotFound,
                          RuntimeJobNotFound)
 from .program.result_decoder import ResultDecoder
@@ -250,12 +250,11 @@ def run(
             raise IBMInputValueError('"image" needs to be in form of image_name:tag')
 
         backend_name = options['backend_name']
-        params_str = json.dumps(inputs, cls=RuntimeEncoder)
         result_decoder = result_decoder or ResultDecoder
         response = self._api_client.program_run(program_id=program_id,
                                                 credentials=self._provider.credentials,
                                                 backend_name=backend_name,
-                                                params=params_str,
+                                                params=inputs,
                                                 image=image)
 
         backend = self._provider.get_backend(backend_name)