Tick size in trading is the smallest price increment a security can move on an exchange. For most U.S. stocks it is one cent, for stocks priced under a dollar it drops to $0.0001, and for futures, options, Treasuries, and currencies it varies by contract. That minimum increment sets a floor on how tightly bid and ask prices can compete, which is why it directly affects what you pay when you buy and what you receive when you sell.
The Penny Grid for U.S. Stocks
If a stock trades at $45.00, the next possible price level is $45.01. That one-cent gap is the tick size for any stock quoted at a dollar or above. Every limit order and every displayed bid and offer on a lit U.S. exchange snaps to this grid. You cannot post an order to buy at $45.003 or sell at $44.997, because the quoting rules prohibit it.
Stocks priced below one dollar follow a much finer grid. The minimum increment drops to one-hundredth of a cent ($0.0001), which allows meaningful price movement in securities where a full penny would be an outsized percentage of the share price. A stock at $0.50 can be quoted at $0.5001 rather than needing a two-percent jump to $0.51.
Rule 612 and the Difference Between Quoting and Executing
Rule 612 of Regulation NMS is the federal rule that sets these quoting floors. It prohibits exchanges, broker-dealers, and alternative trading systems from displaying, ranking, or accepting orders in increments smaller than one cent for stocks priced at a dollar or more, and smaller than $0.0001 for stocks priced below a dollar.1U.S. Securities and Exchange Commission. Responses to Frequently Asked Questions Concerning Rule 612 (Minimum Pricing Increment) of Regulation NMS Without it, traders could step ahead of existing limit orders by offering a price improvement so small it has no real economic value, gaining priority in the order queue for a fraction of a cent.
One distinction trips people up. Rule 612 governs displayed quotes, not trade executions. A broker-dealer can execute your order at a sub-penny price as long as that execution did not originate from an order or quote that was itself priced in a prohibited sub-penny increment.1U.S. Securities and Exchange Commission. Responses to Frequently Asked Questions Concerning Rule 612 (Minimum Pricing Increment) of Regulation NMS This is the legal mechanism behind retail price improvement. When a wholesaler fills your market order at $45.0037 instead of the $45.01 ask, that sub-penny execution is permitted even though a sub-penny quote would not be.
Why Tick Size Matters for What You Pay
A stock is considered tick-constrained when the mandated minimum increment is wider than the spread that natural market forces would produce. These tend to be heavily traded, lower-priced names where the bid-ask spread sits at exactly one cent almost all the time, not because a penny is the fair spread, but because the rules will not let it go lower.
The consequences are real. When liquidity providers cannot compete by offering a tighter price, they compete by being faster. That drives investment in low-latency infrastructure and shapes exchange fee structures designed to attract speed-sensitive order flow. During volatile moments, market makers in tick-constrained stocks control risk by pulling shares off the best bid or offer rather than widening the spread, so displayed size can evaporate exactly when you need it most.
Half-Penny Ticks Arriving November 2026
In September 2024, the SEC adopted amendments to Regulation NMS that overhaul the one-size-fits-all penny tick. Stocks with a time-weighted average quoted spread (TWAS) of $0.015 or less will shift to a half-penny ($0.005) minimum quoting increment. Stocks with a TWAS above $0.015 stay at the one-cent tick.2Federal Register. Regulation NMS: Minimum Pricing Increments, Access Fees, and Transparency of Better Priced Orders The increment for stocks below one dollar remains $0.0001.
TWAS is essentially an average of how wide the bid-ask spread has been over a measurement window. If a stock’s spread consistently sits at one cent, that signals the penny tick is too coarse for the natural supply and demand. Allowing half-penny quotes gives liquidity providers room to compete on price rather than just speed.
The original compliance date was November 2025, but the SEC granted temporary exemptive relief pushing implementation to the first business day of November 2026.3Securities and Exchange Commission. Order Granting Temporary Exemptive Relief from Compliance with Rule 610(c), Rule 610(d) and Rule 612 of Regulation NMS, as Amended Until then, the current framework remains in force.
Access Fees and Round Lots Change Too
The same rule package cuts the maximum per-share access fee exchanges can charge from $0.003 to $0.001 for stocks priced at a dollar or more, and to 0.1 percent of the quote price for stocks below a dollar.3Securities and Exchange Commission. Order Granting Temporary Exemptive Relief from Compliance with Rule 610(c), Rule 610(d) and Rule 612 of Regulation NMS, as Amended Access fees influence the effective cost of trading and the economics of the exchange rebates that pay brokers for routing orders.
Round lot definitions also change based on share price. Stocks at $250 or less keep the traditional 100-share round lot. Stocks priced between $250.01 and $1,000 drop to 40 shares, those between $1,000.01 and $10,000 drop to 10 shares, and anything above $10,000 per share treats a single share as a round lot.4Securities and Exchange Commission. Self-Regulatory Organizations; 24X National Exchange LLC; Notice of Filing and Immediate Effectiveness of Proposed Rule Change to Amend Exchange Rule 11.6(q)(1) For high-priced stocks, this means odd-lot orders that previously fell outside the protected quote system will receive better execution protections.
Tick Sizes in Futures, Treasuries, Options, Bonds, and Forex
Equities get the most regulatory attention, but tick conventions vary widely across other markets. Each asset class is shaped by contract design, trading volume, and historical practice.
Futures
Futures contracts set their own minimum price fluctuation in the specifications published by the listing exchange. The E-mini S&P 500 has a multiplier of $50 times the index value.5CME Group. E-mini S&P 500 Futures Overview Its tick size is 0.25 index points, so each tick is worth $12.50 per contract. Crude oil futures tick in pennies per barrel. Treasury futures use fractions of 32nds of a point.
U.S. Treasury Securities
Treasury pricing looks archaic next to equities. Prices are quoted as a percentage of par value, with fractional components in 32nds of a point. A 30-year Treasury bond future quoted at 134-01 means 134 full points plus 1/32 of a point, or 134.03125 in decimal terms.6CME Group. Calculating U.S. Treasury Pricing In the cash market, a third digit after the dash represents sub-increments of a 32nd: a “+” means half of 1/32, while “2” and “6” mean one-quarter and three-quarters of 1/32. For a $100,000 face-value contract, each full 1/32 tick equals $31.25.
Options
Options markets default to a nickel ($0.05) increment for contracts trading below $3.00 and a dime ($0.10) for those at $3.00 or above.7Nasdaq Listing Center. Nasdaq Options 3 – Section: Minimum Increments Under the Penny Pilot Program, the 300 most actively traded multiply-listed option classes trade in one-cent increments instead.8Federal Register. Self-Regulatory Organizations; Cboe Exchange, Inc.; Notice of Filing and Immediate Effectiveness of a Proposed Rule Change If you trade options on Apple or SPY, you are almost certainly seeing penny-wide quotes. On a less active underlying, the wider nickel or dime increment kicks in.
Corporate Bonds
U.S. corporate bonds have no mandated minimum tick size. Prices are reported through FINRA’s TRACE system as a percentage of par value, and the system accommodates precision up to six decimal places.9Financial Industry Regulatory Authority (FINRA). Frequently Asked Questions (FAQ) about the Trade Reporting and Compliance Engine (TRACE) In practice, most investment-grade bonds trade in increments driven by dealer convention and negotiation rather than exchange rules.
Foreign Exchange
Currency markets use their own terminology. A pip is generally the fourth decimal place in a currency pair, so if EUR/USD moves from 1.0850 to 1.0851, that is one pip. A pipette, sometimes called a fractional pip, is the fifth decimal place. Japanese yen pairs are the main exception, where a pip represents the second decimal place because of the yen’s lower relative value. These conventions are market practice rather than regulatory mandate, and most retail forex platforms quote in pipettes by default.
Calculating What a Tick Is Worth
Knowing the tick size is only half the picture. What you actually need is the dollar value of each tick, because that determines how much money is at stake per contract or per share.
The formula is straightforward: multiply the tick size by the contract multiplier. For the E-mini S&P 500, that is 0.25 × $50 = $12.50 per tick. For the 30-year Treasury bond future, it is 1/32 × $1,000 = $31.25 per tick. For equities, the tick value is one cent per share, which becomes meaningful when you multiply by position size. A 10,000-share position moves $100 with every penny tick.
A point and a tick are different measurements, and they get confused constantly. A point is the smallest whole-number price change, meaning one full dollar on a stock or one full index point on a futures contract. A tick is the smallest possible price change within that framework. In the E-mini, it takes four ticks (each 0.25 points) to move one full point, and a full point is worth $50. Getting this wrong when you set a stop-loss order can mean risking four times what you intended.