diff --git a/src/utils/ContractUtils.ts b/src/utils/ContractUtils.ts
index 77fd387b..bec5bd86 100644
--- a/src/utils/ContractUtils.ts
+++ b/src/utils/ContractUtils.ts
@@ -85,7 +85,7 @@ export async function estimateGas(
   from: string,
   functionToEstimateGas: Function,
   ...args: any[]
-): Promise<any> {
+): Promise<number> {
   let estimatedGas = GASLIMIT_DEFAULT
   try {
     estimatedGas = await functionToEstimateGas.apply(null, args).estimateGas(