How to Protect Yourself from MEV: Sandwich Attacks, Front-Running & Private Transactions

Published February 1, 2026 · Updated March 7, 2026 · By JaredFromSubway

Types of MEV Attacks Targeting Regular Users

There are three primary forms of MEV extraction that affect everyday DeFi participants. Understanding them is the first step toward defending against them.

1. Sandwich Attacks

A sandwich attack is the most common and damaging form of MEV extraction. The attacker spots your pending swap in the mempool, places a buy order before your trade (front-run) to push the price up, lets your trade execute at the inflated price, and then sells immediately after (back-run) to capture the difference. Your trade is "sandwiched" between the attacker's two transactions. According to data tracked by JaredFromSubway, sandwich attacks accounted for $289 million in attack volume during 2025, with more than 33,000 victims in March 2025 alone.

2. Front-Running

Front-running occurs when a bot detects a profitable pending transaction and submits an identical or similar transaction with a higher gas fee so that it executes first. This is particularly common with NFT mints, token launches, and large DEX trades. The front-runner profits by acting on information that is public in the mempool but has not yet been confirmed on-chain.

3. Back-Running

Back-running involves placing a transaction immediately after a target transaction to capitalize on the state change it creates. This is common in arbitrage scenarios: a large trade creates a price discrepancy between pools, and the back-runner captures the arbitrage opportunity. While less harmful to individual users than sandwich attacks, back-running still represents value that could have gone to you or to the protocol.

How Sandwich Attacks Drain Your Trades: The Math

To understand why sandwich attacks work, you need to understand the constant product formula used by AMMs like Uniswap: x * y = k

Here, x is the reserve of token A, y is the reserve of token B, and k is the constant product. When you buy token B with token A, you add to x and remove from y, but k must stay constant.

For a deeper exploration of the mechanics, see our article on how sandwich attacks work.

This is not a theoretical scenario. The JaredFromSubway MEV bot and similar bots execute thousands of these attacks daily. The larger your trade and the higher your slippage tolerance, the more profitable you are as a target.

5 Proven Methods to Protect Yourself from MEV

Method 1: Flashbots Protect RPC

Flashbots Protect is a free, private transaction relay that sends your transactions directly to block builders instead of broadcasting them to the public mempool. Since MEV bots cannot see your transaction before it is included in a block, they cannot sandwich or front-run you.

How to add Flashbots Protect to MetaMask:

1. Open MetaMask and click the network dropdown at the top.
2. Select "Add network" → "Add a network manually."
3. Enter the following details:
   • Network Name: Flashbots Protect
   • New RPC URL: https://rpc.flashbots.net
   • Chain ID: 1
   • Currency Symbol: ETH
   • Block Explorer: https://etherscan.io
4. Click "Save" and switch to the Flashbots Protect network.
5. All transactions you submit through this RPC will bypass the public mempool entirely.

Pros: Free, easy to set up, prevents all mempool-based MEV attacks.
Cons: Transactions may take slightly longer to be included. Only works on Ethereum mainnet.

Method 2: MEV Blocker by CoW Protocol

MEV Blocker is a service developed by CoW Protocol, Beaver Build, and Agnostic Relay. It routes your transactions through a network of searchers who compete to back-run your transaction (which is benign arbitrage) while blocking harmful front-running and sandwich attacks. The key benefit: you actually receive a rebate from the back-running profits.

To use MEV Blocker, add https://rpc.mevblocker.io as a custom RPC in MetaMask using the same steps described above for Flashbots Protect. MEV Blocker supports Ethereum mainnet with chain ID 1.

Pros: Blocks sandwich attacks, provides MEV rebates to users, supported by major builders.
Cons: Rebates can be small for low-value transactions. Ethereum mainnet only.

Method 3: Low Slippage Tolerance Settings

This is the simplest and most effective change you can make right now. Your slippage tolerance determines the maximum price deviation you are willing to accept for your trade. MEV bots specifically look for transactions with high slippage tolerance because there is more room to extract profit.

On Uniswap: Click the gear icon before confirming your swap. Set slippage to 0.5% or lower for stablecoin pairs and 1-2% for volatile tokens. Avoid setting slippage above 3% unless absolutely necessary (e.g., high-tax tokens).

When JaredFromSubway scans the mempool, trades with slippage above 3% are the most profitable targets. By setting your slippage to 0.5%, you make the potential profit so small that the gas cost of executing the sandwich exceeds the gain, effectively making your trade unprofitable to attack.

Pros: Works on any DEX, any chain, no setup required.
Cons: Very low slippage may cause trades to fail during periods of high volatility.

Method 4: Private Transaction Services

Beyond Flashbots Protect and MEV Blocker, several other private transaction services exist. These include direct submission endpoints offered by major block builders like Titan Builder, rsync builder, and BloXroute. Some wallets now integrate private transactions natively — Rabby Wallet, for instance, offers a one-click option to send transactions privately.

The concept is the same across all these services: your transaction never enters the public mempool. Instead, it goes directly to block builders through a private channel. Since MEV bots surveil the public mempool, keeping your transaction out of it eliminates the attack surface entirely.

For users on Layer 2 networks like Arbitrum, Base, or Optimism, the sequencer model already provides partial protection against MEV because transactions are ordered by the sequencer rather than being visible in a public mempool. However, sequencer-level MEV extraction is still possible and is an evolving area.

Pros: Comprehensive protection, multiple providers to choose from.
Cons: Requires trust in the private relay operator. Some services are Ethereum-mainnet only.

Method 5: Using DEX Aggregators (1inch, CoW Swap)

DEX aggregators split your trade across multiple liquidity sources, reducing the price impact on any single pool. This alone makes sandwich attacks less profitable. But some aggregators go further with built-in MEV protection.

CoW Swap uses a batch auction mechanism where trades are matched off-chain by "solvers" competing to find the best execution. Your order never hits an on-chain AMM directly, so there is no mempool transaction to sandwich. CoW Swap also offers surplus — if the solver finds a better price than your limit, you keep the difference.

1inch Fusion uses a similar model with resolvers executing trades via limit orders, bypassing the public mempool. The 1inch Fusion mode is specifically designed to be MEV-resistant and often provides gas-free execution.

Pros: Best price execution across DEXs, built-in MEV protection, often gas-free.
Cons: Trades may take longer (batch auctions). Not ideal for time-sensitive transactions.

Why JaredFromSubway Publishes This Guide

You might wonder why a MEV bot operation would publish a guide teaching users how to avoid being exploited. The answer is transparency.

JaredFromSubway has always operated with the philosophy that MEV is a structural feature of blockchain architecture, not a bug. The public mempool is, by design, public. The constant product AMM formula creates mathematically predictable price impact. MEV extraction is the natural consequence of these design choices.

However, informed users should not be victims. The JaredFromSubway bot targets high-slippage trades — transactions where users set 5%, 10%, or even 49% slippage tolerance, often unknowingly. These trades broadcast a clear signal that the user is willing to accept massive price deviation, making them ideal targets.

By publishing this guide, JaredFromSubway aims to educate the DeFi community. If every user set their slippage to 0.5% and used a private RPC, sandwich attacks would become economically unviable. The MEV ecosystem would shift entirely to benign forms like arbitrage, which actually improves market efficiency. We believe that outcome is better for everyone — including us.

Protection is simple. The five methods above cost nothing to implement and take minutes to set up. There is no reason for any DeFi user to remain unprotected in 2026.

MEV Attack Statistics: The Scale of the Problem

These figures reflect only Ethereum mainnet sandwich attacks tracked through public block data. The true figure across all EVM chains — including Arbitrum, Base, BSC, and Polygon — is substantially higher. MEV extraction is not slowing down. As DeFi volume grows, so does the MEV opportunity set. The only reliable defense is user-side protection.

Frequently Asked Questions