diff --git a/rpc-client/src/nonblocking/rpc_client.rs b/rpc-client/src/nonblocking/rpc_client.rs
index bb1c7fa21e..1ea8d7dd59 100644
--- a/rpc-client/src/nonblocking/rpc_client.rs
+++ b/rpc-client/src/nonblocking/rpc_client.rs
@@ -1473,6 +1473,8 @@ impl RpcClient {
             bundle,
             RpcSimulateBundleConfig {
                 simulation_bank: Some(SimulationSlotConfig::Commitment(self.commitment())),
+                pre_execution_accounts_configs: vec![None; bundle.transactions.len()],
+                post_execution_accounts_configs: vec![None; bundle.transactions.len()],
                 ..RpcSimulateBundleConfig::default()
             },
         )
diff --git a/rpc/src/rpc.rs b/rpc/src/rpc.rs
index 2e7918fcba..085cf79b06 100644
--- a/rpc/src/rpc.rs
+++ b/rpc/src/rpc.rs
@@ -3441,6 +3441,7 @@ pub mod rpc_full {
         super::*,
         crate::rpc::utils::{build_simulate_bundle_params, rpc_bundle_result_from_bank_result},
         itertools::izip,
+        solana_runtime::bank::SimulateBundleError,
         solana_sdk::message::{SanitizedVersionedMessage, VersionedMessage},
     };
 
@@ -3606,6 +3607,14 @@ pub mod rpc_full {
         ) -> Result<Vec<RpcPrioritizationFee>>;
     }
 
+    fn jsonrpc_error_from_simulate_bundle_error(e: SimulateBundleError) -> Error {
+        match e {
+            SimulateBundleError::AccountNotFoundInBank(pubkey) => {
+                Error::invalid_params(format!("account {:?} not found in bank", pubkey))
+            }
+        }
+    }
+
     pub struct FullImpl;
     impl Full for FullImpl {
         type Metadata = JsonRpcRequestProcessor;
@@ -4084,10 +4093,7 @@ pub mod rpc_full {
 
             let bank_result = bank
                 .simulate_bundle(sanitized_txs, pre_execution_pks, post_execution_pks)
-                .map_err(|e| {
-                    error!("bank error {}", e);
-                    Error::internal_error()
-                })?;
+                .map_err(jsonrpc_error_from_simulate_bundle_error)?;
 
             let rpc_bundle_result = rpc_bundle_result_from_bank_result(bank_result, config)?;
 
diff --git a/runtime/src/bank.rs b/runtime/src/bank.rs
index 2742b3f1cc..b91132272c 100644
--- a/runtime/src/bank.rs
+++ b/runtime/src/bank.rs
@@ -158,7 +158,6 @@ use {
         cmp::min,
         collections::{HashMap, HashSet},
         convert::{TryFrom, TryInto},
-        error::Error,
         fmt, mem,
         ops::{Deref, RangeInclusive},
         path::PathBuf,
@@ -174,6 +173,7 @@ use {
         thread::Builder,
         time::{Duration, Instant},
     },
+    thiserror::Error,
 };
 
 /// params to `verify_bank_hash`
@@ -523,6 +523,12 @@ pub struct BundleSimulationResult {
     pub transaction_results: Vec<BundleTransactionSimulationResult>,
 }
 
+#[derive(Error, Debug)]
+pub enum SimulateBundleError {
+    #[error("account missing from bank: {0}")]
+    AccountNotFoundInBank(Pubkey),
+}
+
 #[derive(Clone)]
 pub struct BundleTransactionSimulationResult {
     pub result: Result<()>,
@@ -3850,7 +3856,7 @@ impl Bank {
         bundle: Vec<SanitizedTransaction>,
         pre_execution_accounts_requested: Vec<Option<Vec<Pubkey>>>,
         post_execution_accounts_requested: Vec<Option<Vec<Pubkey>>>,
-    ) -> result::Result<BundleSimulationResult, Box<dyn Error>> {
+    ) -> result::Result<BundleSimulationResult, SimulateBundleError> {
         assert_eq!(pre_execution_accounts_requested.len(), bundle.len());
         assert_eq!(post_execution_accounts_requested.len(), bundle.len());
 
@@ -3920,8 +3926,7 @@ impl Bank {
                             Ok(data)
                         } else {
                             self.get_account(pubkey)
-                                // TODO(seg): let's use a concrete error type
-                                .ok_or(format!("pubkey {} does not exist", pubkey))
+                                .ok_or(SimulateBundleError::AccountNotFoundInBank(*pubkey))
                         }?;
                         pre_accounts.push(AccountData {
                             pubkey: *pubkey,