Micro vs E-mini vs E-nano Futures: Contract Sizes and Tick Values Compared

CME Group offers three contract sizes for major U.S. equity indices: standard E-mini, Micro E-mini, and E-nano. Each serves different account sizes and risk tolerances. This guide breaks down the key differences.

Contract Size Hierarchy

The three sizes form a 10:1 ratio chain for S&P 500, Nasdaq-100, and Dow Jones contracts:

Tick Values: Where Size Matters Most

The tick value determines your profit or loss per tick of price movement. This is where contract size directly impacts your risk:

Key insight: E-nano contracts have a larger tick size (0.5 vs 0.25 points) but smaller tick value due to the 1/10 multiplier structure. This means E-nanos move in half-point increments, not quarter-points like ES and MES.

Margin Requirements

CME initial margin requirements (subject to change; verify with your broker):

• ES: ~$12,000-$13,000 per contract
• MES: ~$1,200-$1,300 per contract
• NES: ~$120-$130 per contract (estimated, launched Aug 2026)

Day trading margins are typically 25-50% of overnight margins. Brokers may set higher requirements.

Worked Example: 10-Point Stop on S&P 500

Assume you're trading a 10-point stop with $500 risk budget:

Which Size Should You Trade?

Choose E-mini (ES, NQ, YM, RTY) if:

• Your account is $50,000+ and you want standard liquidity
• Your typical stop losses are 5-20 points
• You're comfortable with $50-100+ risk per tick/contract
• You trade large size and want the deepest order book

Choose Micro (MES, MNQ, MYM, M2K) if:

• Your account is $5,000-$50,000
• You want 10:1 fractional sizing vs E-mini
• You're scaling into positions or managing prop-firm risk rules
• Commissions are reasonable for your trade frequency ($0.50-$1.00/side typical)

Choose E-nano (NES, NNQ, N2K, NDOW) if:

• Your account is under $5,000 or you're testing strategies
• You want ultra-fine position sizing (100 NES = 1 ES)
• You're trading within strict prop-firm daily loss limits
• You accept that tick size is 0.5 points (coarser than ES/MES at 0.25)

Commissions Matter More at Smaller Sizes

A $0.60 round-trip commission represents:

• ES: 1.2% of a 1-point move ($50)
• MES: 12% of a 1-point move ($5)
• NES: 120% of a 1-point move ($0.50)

For E-nanos especially, commission-per-contract becomes a significant percentage of profit per point. If your broker charges $0.50+ per side, a 5-point winner on NES ($2.50 gross) loses 40%+ to fees. Negotiate lower rates or trade larger sizes if commissions eat your edge.

Liquidity Differences

E-mini contracts (ES, NQ) have the deepest liquidity — thousands of contracts at each price level during RTH. Slippage is minimal even on larger orders.

Micro contracts (MES, MNQ) have good liquidity but narrower order books. Expect 1-tick slippage on market orders above ~20-30 contracts during RTH.

E-nano contracts (NES, NNQ) launched August 2026 and are still building liquidity. Bid-ask spreads may be wider, and large orders (100+ contracts) can move the market. Use limit orders.

Using the Position Size Calculator

Calculate your exact position size for any of these contracts using the futures position size calculator. Enter your risk budget, stop distance, and select MES, ES, or NES to see how many contracts fit your risk parameters.

Disclosure: This site is maintained by a trader who also develops Edge Trader Tools, a NinjaTrader add-on for automated position sizing. The calculator is free and independent.