diff --git a/src/__swaps__/screens/Swap/hooks/useEstimatedGasFee.ts b/src/__swaps__/screens/Swap/hooks/useEstimatedGasFee.ts
index 9f8af50f901..17fb0d613a8 100644
--- a/src/__swaps__/screens/Swap/hooks/useEstimatedGasFee.ts
+++ b/src/__swaps__/screens/Swap/hooks/useEstimatedGasFee.ts
@@ -19,9 +19,22 @@ function safeBigInt(value: string) {
   }
 }
 
+const isFeeNaN = (value: string | undefined) => isNaN(Number(value)) || typeof value === 'undefined';
+
 export function calculateGasFee(gasSettings: GasSettings, gasLimit: string) {
-  const amount = gasSettings.isEIP1559 ? add(gasSettings.maxBaseFee, gasSettings.maxPriorityFee || '0') : gasSettings.gasPrice;
-  return multiply(gasLimit, amount);
+  if (gasSettings.isEIP1559) {
+    if (isFeeNaN(gasSettings.maxBaseFee) || isFeeNaN(gasSettings.maxPriorityFee)) {
+      return null;
+    }
+
+    return add(gasSettings.maxBaseFee, gasSettings.maxPriorityFee);
+  }
+
+  if (isFeeNaN(gasSettings.gasPrice)) {
+    return null;
+  }
+
+  return multiply(gasLimit, gasSettings.gasPrice);
 }
 
 export function useEstimatedGasFee({
@@ -40,6 +53,7 @@ export function useEstimatedGasFee({
     if (!gasLimit || !gasSettings || !nativeNetworkAsset?.price) return;
 
     const fee = calculateGasFee(gasSettings, gasLimit);
+    if (!fee) return;
 
     const networkAssetPrice = nativeNetworkAsset.price.value?.toString();
     if (!networkAssetPrice) return `${formatNumber(weiToGwei(fee))} Gwei`;
diff --git a/src/__swaps__/screens/Swap/providers/SyncSwapStateAndSharedValues.tsx b/src/__swaps__/screens/Swap/providers/SyncSwapStateAndSharedValues.tsx
index 843fcc616d6..fa047483948 100644
--- a/src/__swaps__/screens/Swap/providers/SyncSwapStateAndSharedValues.tsx
+++ b/src/__swaps__/screens/Swap/providers/SyncSwapStateAndSharedValues.tsx
@@ -79,10 +79,28 @@ export const SyncQuoteSharedValuesToState = () => {
   return null;
 };
 
+const isFeeNaNWorklet = (value: string | undefined) => {
+  'worklet';
+
+  return isNaN(Number(value)) || typeof value === 'undefined';
+};
+
 export function calculateGasFeeWorklet(gasSettings: GasSettings, gasLimit: string) {
   'worklet';
-  const amount = gasSettings.isEIP1559 ? sumWorklet(gasSettings.maxBaseFee, gasSettings.maxPriorityFee || '0') : gasSettings.gasPrice;
-  return mulWorklet(gasLimit, amount);
+
+  if (gasSettings.isEIP1559) {
+    if (isFeeNaNWorklet(gasSettings.maxBaseFee) || isFeeNaNWorklet(gasSettings.maxPriorityFee)) {
+      return null;
+    }
+
+    return sumWorklet(gasSettings.maxBaseFee || '0', gasSettings.maxPriorityFee || '0');
+  }
+
+  if (isFeeNaNWorklet(gasSettings.gasPrice)) {
+    return null;
+  }
+
+  return mulWorklet(gasLimit, gasSettings.gasPrice);
 }
 
 export function formatUnitsWorklet(value: string, decimals: number) {
@@ -166,12 +184,23 @@ export function SyncGasStateToSharedValues() {
       hasEnoughFundsForGas.value = undefined;
       if (!gasSettings || !estimatedGasLimit || !quote || 'error' in quote || isLoadingNativeNetworkAsset) return;
 
+      // NOTE: if we don't have a gas price or max base fee or max priority fee, we can't calculate the gas fee
+      if (
+        (gasSettings.isEIP1559 && !(gasSettings.maxBaseFee || gasSettings.maxPriorityFee)) ||
+        (!gasSettings.isEIP1559 && !gasSettings.gasPrice)
+      ) {
+        return;
+      }
+
       if (!userNativeNetworkAsset) {
         hasEnoughFundsForGas.value = false;
         return;
       }
 
       const gasFee = calculateGasFeeWorklet(gasSettings, estimatedGasLimit);
+      if (gasFee === null || isNaN(Number(gasFee))) {
+        return;
+      }
 
       const nativeGasFee = divWorklet(gasFee, powWorklet(10, userNativeNetworkAsset.decimals));
 
diff --git a/src/handlers/web3.ts b/src/handlers/web3.ts
index 13416a8aceb..015e75eea6d 100644
--- a/src/handlers/web3.ts
+++ b/src/handlers/web3.ts
@@ -370,6 +370,10 @@ export async function estimateGasWithPadding(
       ? contractCallEstimateGas(...(callArguments ?? []), txPayloadToEstimate)
       : p.estimateGas(cleanTxPayload));
 
+    if (!BigNumber.isBigNumber(estimatedGas)) {
+      throw new Error('Invalid gas limit type');
+    }
+
     const lastBlockGasLimit = addBuffer(gasLimit.toString(), 0.9);
     const paddedGas = addBuffer(estimatedGas.toString(), paddingFactor.toString());
     logger.debug('[web3]: ⛽ GAS CALCULATIONS!', {
diff --git a/src/raps/actions/crosschainSwap.ts b/src/raps/actions/crosschainSwap.ts
index ddbd4789be3..eeca43b96e2 100644
--- a/src/raps/actions/crosschainSwap.ts
+++ b/src/raps/actions/crosschainSwap.ts
@@ -71,9 +71,13 @@ export const estimateCrosschainSwapGasLimit = async ({
       SWAP_GAS_PADDING
     );
 
-    return gasLimit || getCrosschainSwapDefaultGasLimit(quote);
+    if (gasLimit === null || gasLimit === undefined || isNaN(Number(gasLimit))) {
+      return getCrosschainSwapDefaultGasLimit(quote) || getDefaultGasLimitForTrade(quote, chainId);
+    }
+
+    return gasLimit;
   } catch (error) {
-    return getCrosschainSwapDefaultGasLimit(quote);
+    return getCrosschainSwapDefaultGasLimit(quote) || getDefaultGasLimitForTrade(quote, chainId);
   }
 };
 
diff --git a/src/raps/actions/swap.ts b/src/raps/actions/swap.ts
index 2b1eddb690c..179f8ae7d27 100644
--- a/src/raps/actions/swap.ts
+++ b/src/raps/actions/swap.ts
@@ -93,9 +93,13 @@ export const estimateSwapGasLimit = async ({
         WRAP_GAS_PADDING
       );
 
-      return gasLimit || String(quote?.defaultGasLimit) || String(default_estimate);
+      if (gasLimit === null || gasLimit === undefined || isNaN(Number(gasLimit))) {
+        return quote?.defaultGasLimit || default_estimate;
+      }
+
+      return gasLimit;
     } catch (e) {
-      return String(quote?.defaultGasLimit) || String(default_estimate);
+      return quote?.defaultGasLimit || default_estimate;
     }
     // Swap
   } else {
@@ -116,8 +120,11 @@ export const estimateSwapGasLimit = async ({
       }
 
       const gasLimit = await estimateGasWithPadding(params, method, methodArgs, provider, SWAP_GAS_PADDING);
+      if (gasLimit === null || gasLimit === undefined || isNaN(Number(gasLimit))) {
+        return getDefaultGasLimitForTrade(quote, chainId);
+      }
 
-      return gasLimit || getDefaultGasLimitForTrade(quote, chainId);
+      return gasLimit;
     } catch (error) {
       return getDefaultGasLimitForTrade(quote, chainId);
     }
diff --git a/src/raps/actions/unlock.ts b/src/raps/actions/unlock.ts
index b4377935b99..b2de3ff610c 100644
--- a/src/raps/actions/unlock.ts
+++ b/src/raps/actions/unlock.ts
@@ -91,7 +91,12 @@ export const estimateApprove = async ({
     const gasLimit = await tokenContract.estimateGas.approve(spender, MaxUint256, {
       from: owner,
     });
-    return gasLimit ? gasLimit.toString() : `${gasUnits.basic_approval}`;
+
+    if (gasLimit === null || gasLimit === undefined || isNaN(Number(gasLimit.toString()))) {
+      return `${gasUnits.basic_approval}`;
+    }
+
+    return gasLimit.toString();
   } catch (error) {
     logger.error(new RainbowError('[raps/unlock]: error estimateApprove'), {
       message: (error as Error)?.message,
diff --git a/src/raps/unlockAndCrosschainSwap.ts b/src/raps/unlockAndCrosschainSwap.ts
index d1ff8fa64f3..a5d3b20ed21 100644
--- a/src/raps/unlockAndCrosschainSwap.ts
+++ b/src/raps/unlockAndCrosschainSwap.ts
@@ -53,10 +53,8 @@ export const estimateUnlockAndCrosschainSwap = async ({
     });
   }
 
-  let unlockGasLimit;
-
   if (swapAssetNeedsUnlocking) {
-    unlockGasLimit = await estimateApprove({
+    const unlockGasLimit = await estimateApprove({
       owner: accountAddress,
       tokenAddress: sellTokenAddress,
       spender: allowanceTarget,
@@ -71,7 +69,14 @@ export const estimateUnlockAndCrosschainSwap = async ({
     quote,
   });
 
+  if (swapGasLimit === null || swapGasLimit === undefined || isNaN(Number(swapGasLimit))) {
+    return null;
+  }
+
   const gasLimit = gasLimits.concat(swapGasLimit).reduce((acc, limit) => add(acc, limit), '0');
+  if (isNaN(Number(gasLimit))) {
+    return null;
+  }
 
   return gasLimit.toString();
 };
diff --git a/src/raps/unlockAndSwap.ts b/src/raps/unlockAndSwap.ts
index cdf9349adcb..769546efec6 100644
--- a/src/raps/unlockAndSwap.ts
+++ b/src/raps/unlockAndSwap.ts
@@ -43,7 +43,6 @@ export const estimateUnlockAndSwap = async ({
   let swapAssetNeedsUnlocking = false;
 
   const nativeAsset = isLowerCaseMatch(ETH_ADDRESS_AGGREGATOR, sellTokenAddress) || isNativeAsset(sellTokenAddress, chainId);
-
   if (!isNativeAssetUnwrapping && !nativeAsset) {
     swapAssetNeedsUnlocking = await assetNeedsUnlocking({
       owner: accountAddress,
@@ -65,12 +64,8 @@ export const estimateUnlockAndSwap = async ({
     if (gasLimitFromMetadata) {
       return gasLimitFromMetadata;
     }
-  }
 
-  let unlockGasLimit;
-
-  if (swapAssetNeedsUnlocking) {
-    unlockGasLimit = await estimateApprove({
+    const unlockGasLimit = await estimateApprove({
       owner: accountAddress,
       tokenAddress: sellTokenAddress,
       spender: getRainbowRouterContractAddress(chainId),
@@ -85,7 +80,14 @@ export const estimateUnlockAndSwap = async ({
     quote,
   });
 
+  if (swapGasLimit === null || swapGasLimit === undefined || isNaN(Number(swapGasLimit))) {
+    return null;
+  }
+
   const gasLimit = gasLimits.concat(swapGasLimit).reduce((acc, limit) => add(acc, limit), '0');
+  if (isNaN(Number(gasLimit))) {
+    return null;
+  }
 
   return gasLimit.toString();
 };