diff --git a/src/wallet/Wallet.interfaces.ts b/src/wallet/Wallet.interfaces.ts
index 8f292871..daf03a11 100644
--- a/src/wallet/Wallet.interfaces.ts
+++ b/src/wallet/Wallet.interfaces.ts
@@ -500,13 +500,13 @@ export interface ListActionsResult {
 }
 
 /**
- * @param {Base64String} derivationPrefix - Payment-level derivation prefix used by the sender for key derivation (for payments).
- * @param {Base64String} derivationSuffix - Specific output-level derivation suffix used by the sender for key derivation (for payments).
+ * @param {string} derivationPrefix - Payment-level derivation prefix used by the sender for key derivation (for payments).
+ * @param {string} derivationSuffix - Specific output-level derivation suffix used by the sender for key derivation (for payments).
  * @param {PubKeyHex} senderIdentityKey - Public identity key of the sender (for payments).
  */
 export interface WalletPayment {
-  derivationPrefix: Base64String
-  derivationSuffix: Base64String
+  derivationPrefix: string
+  derivationSuffix: string
   senderIdentityKey: PubKeyHex
 }
 
diff --git a/src/wallet/substrates/WalletWireProcessor.ts b/src/wallet/substrates/WalletWireProcessor.ts
index 243400dd..277bad4f 100644
--- a/src/wallet/substrates/WalletWireProcessor.ts
+++ b/src/wallet/substrates/WalletWireProcessor.ts
@@ -819,7 +819,7 @@ export default class WalletWireProcessor implements WalletWire {
               const derivationPrefixBytes = paramsReader.read(
                 derivationPrefixLength
               )
-              output.paymentRemittance.derivationPrefix = Utils.toBase64(
+              output.paymentRemittance.derivationPrefix = Utils.toUTF8(
                 derivationPrefixBytes
               )
 
@@ -828,7 +828,7 @@ export default class WalletWireProcessor implements WalletWire {
               const derivationSuffixBytes = paramsReader.read(
                 derivationSuffixLength
               )
-              output.paymentRemittance.derivationSuffix = Utils.toBase64(
+              output.paymentRemittance.derivationSuffix = Utils.toUTF8(
                 derivationSuffixBytes
               )
             } else if (protocolFlag === 2) {
diff --git a/src/wallet/substrates/WalletWireTransceiver.ts b/src/wallet/substrates/WalletWireTransceiver.ts
index 7dcbdafd..7776b0c1 100644
--- a/src/wallet/substrates/WalletWireTransceiver.ts
+++ b/src/wallet/substrates/WalletWireTransceiver.ts
@@ -843,13 +843,13 @@ export default class WalletWireTransceiver implements WalletInterface {
         )
         const derivationPrefixAsArray = Utils.toArray(
           out.paymentRemittance.derivationPrefix,
-          'base64'
+          'utf8'
         )
         paramWriter.writeVarIntNum(derivationPrefixAsArray.length)
         paramWriter.write(derivationPrefixAsArray)
         const derivationSuffixAsArray = Utils.toArray(
           out.paymentRemittance.derivationSuffix,
-          'base64'
+          'utf8'
         )
         paramWriter.writeVarIntNum(derivationSuffixAsArray.length)
         paramWriter.write(derivationSuffixAsArray)