diff --git a/packages/txwrapper-core/src/core/decode/decodeSigningPayload.ts b/packages/txwrapper-core/src/core/decode/decodeSigningPayload.ts
index 3b80b670..c557b7c1 100644
--- a/packages/txwrapper-core/src/core/decode/decodeSigningPayload.ts
+++ b/packages/txwrapper-core/src/core/decode/decodeSigningPayload.ts
@@ -55,15 +55,18 @@ export function decodeSigningPayload(
 		? payload.era.asMortalEra.period.toNumber()
 		: 0;
 
-	let assetId: number | undefined;
+	let assetId: number | object | undefined;
 	if (payload.inner.assetId) {
-		assetId = payload.inner.assetId.isSome
-			? parseInt(payload.inner.assetId.toString())
-			: undefined;
+		assetId = payload.inner.assetId.isSome ? payload.inner.assetId : undefined;
 	}
 
 	return {
-		assetId,
+		assetId:
+			typeof assetId === 'object'
+				? assetId
+				: typeof assetId === 'number'
+				? parseInt(assetId.toString())
+				: undefined,
 		blockHash: payload.blockHash.toHex(),
 		eraPeriod,
 		genesisHash: payload.genesisHash.toHex(),
diff --git a/packages/txwrapper-core/src/core/decode/decodeUnsignedTx.ts b/packages/txwrapper-core/src/core/decode/decodeUnsignedTx.ts
index d7e92d69..df9b4ece 100644
--- a/packages/txwrapper-core/src/core/decode/decodeUnsignedTx.ts
+++ b/packages/txwrapper-core/src/core/decode/decodeUnsignedTx.ts
@@ -43,12 +43,13 @@ export function decodeUnsignedTx(
 	const eraPeriod = isImmortalEra
 		? hexToNumber(registry.createType('ImmortalEra', unsigned.era).toHex())
 		: registry.createType('MortalEra', unsigned.era).period.toNumber();
-
+	const assetId = unsigned.assetId;
 	return {
 		address: unsigned.address,
-		assetId: registry
-			.createType('Compact<AssetId>', unsigned.assetId)
-			.toNumber(),
+		assetId:
+			typeof assetId === 'object'
+				? registry.createType('MultiLocation', assetId)
+				: registry.createType('Compact<AssetId>', assetId).toNumber(),
 		blockHash: unsigned.blockHash,
 		blockNumber: registry
 			.createType('BlockNumber', unsigned.blockNumber)
diff --git a/packages/txwrapper-core/src/core/method/defineMethod.ts b/packages/txwrapper-core/src/core/method/defineMethod.ts
index b6e8ce81..b0331a58 100644
--- a/packages/txwrapper-core/src/core/method/defineMethod.ts
+++ b/packages/txwrapper-core/src/core/method/defineMethod.ts
@@ -156,10 +156,14 @@ export function defineMethod(
 	const extrinsicEra = createEra(registry, eraOptions);
 	const blockHash = info.blockHash as `0x${string}`;
 	const genesisHash = info.genesisHash as `0x${string}`;
+	const assetId = info.assetId;
 
 	return {
 		address: info.address,
-		assetId: registry.createType('Compact<AssetId>', info.assetId).toNumber(),
+		assetId:
+			typeof assetId === 'object'
+				? registry.createType('MultiLocation', assetId)
+				: registry.createType('Compact<AssetId>', assetId).toNumber(),
 		blockHash,
 		blockNumber: registry.createType('BlockNumber', info.blockNumber).toHex(),
 		era: extrinsicEra.toHex(),
diff --git a/packages/txwrapper-core/src/types/method.ts b/packages/txwrapper-core/src/types/method.ts
index a26ff5b2..829f9a08 100644
--- a/packages/txwrapper-core/src/types/method.ts
+++ b/packages/txwrapper-core/src/types/method.ts
@@ -69,9 +69,8 @@ export interface UnsignedTransaction extends SignerPayloadJSON {
 	/**
 	 * The assetId used in ChargeAssetTxPayment
 	 *
-	 * @default 0
 	 */
-	assetId?: number;
+	assetId?: number | object;
 	/**
 	 * The SCALE-encoded metadata, as a hex string. Can be retrieved via the RPC
 	 * call `state_getMetadata`.
@@ -90,9 +89,8 @@ export interface BaseTxInfo {
 	/**
 	 * The assetId used in ChargeAssetTxPayment
 	 *
-	 * @default 0
 	 */
-	assetId?: number;
+	assetId?: number | object;
 	/**
 	 * The checkpoint hash of the block, in hex.
 	 */