ECN fees, rebates and per-share commissions: the scalper's cost hurdle
Adding or removing liquidity changes the exchange fee or rebate on every fill. With commissions and regulatory fees, these set the minimum move a scalp needs to break even.
Start in plain English
"ECN fees" is the trader's name for the per-share fees and rebates that exchanges and other trading venues charge or pay on each fill. An ECN (electronic communication network) was originally a separate electronic venue; today most of these fees come from exchanges, but the name stuck. For a scalper, who aims for a few cents per share, these fees, together with commissions and regulatory fees, decide how far a stock needs to move before a trade breaks even.
The core idea: every fill either adds liquidity or removes it, and that changes what you pay.
- Removing liquidity means your order trades immediately against an order already resting on the book: a market order, or a limit order priced at or through the opposite side. Many venues charge the remover a fee, often called a "take" fee.
- Adding liquidity means your limit order rests on the book and someone else trades against it later. Many venues pay the adder a small rebate.
This is called maker-taker pricing. On top of it come your broker's commission (per share, per trade or tiered) and two regulatory fees on sells: the SEC's Section 31 fee and FINRA's Trading Activity Fee (TAF). Added together, these give a cost per round trip, and dividing it by your share count gives the minimum move in cents the trade needs just to break even.
A worked example: one 8-cent scalp, two sizes, two fee plans
All fee levels and prices here are Illustrative. Quarry Pine Energy is fictional; the two fee plans describe common plan types, not any broker.
The trade. Buy Quarry Pine Energy at $4.00 with a marketable limit order (removes liquidity). Sell at $4.08 with a resting limit order that is filled (adds liquidity). Gross gain: 8 cents per share.
Plan P, per-share pricing. Commission $0.0035 per share per side. Exchange fees passed through: take $0.0030 per share, add rebate $0.0020 per share. Regulatory fees on the sell.
Plan T, per-trade pricing. $4.95 per order, exchange fees included. Regulatory fees on the sell.
Regulatory fees on the sell (rates as of 2026-10-05; see below): Section 31 at $20.60 per million dollars of sale proceeds, and TAF at its scheduled 2027 rate of $0.000195 per share. Each is rounded up to the cent in this example.
| 200 shares (gross $16.00) | 2,000 shares (gross $160.00) | |
|---|---|---|
| Plan P costs | $1.40 commission + $0.20 net exchange fees + $0.06 regulatory = $1.66 | $14.00 + $2.00 + $0.56 = $16.56 |
| Plan P net | $14.34 (costs 10% of gross) | $143.44 (10%) |
| Plan T costs | $9.90 + $0.06 regulatory = $9.96 | $9.90 + $0.56 = $10.46 |
| Plan T net | $6.04 (costs 62% of gross) | $149.54 (7%) |
The same 8-cent move kept 90% of its gross under the per-share plan at either size. Under the per-trade plan it kept 38% at 200 shares and 93% at 2,000. Neither plan is cheaper in general: per-share pricing scales with size, per-trade pricing punishes small orders. Your plan type and your typical size together set the hurdle.
Break-even move. Under Plan P, with a take on entry and an add on exit, costs come to about 0.83 cents per share. Under Plan T they are about 4.98 cents per share at 200 shares and 0.52 cents at 2,000 (computed, Illustrative). A trader with Plan T and 200-share size needs a 5-cent move just to cover costs.
Two paths from the same plan
All numbers here are Illustrative.
The plan. Quarry Pine Energy, Plan P, 2,000 shares. Buy at the $4.00 ask (removes liquidity). Stop $3.96, so 1R = $80. Target $4.08 with a resting sell limit (adds liquidity if filled). Time stop five minutes.
Path AThe resting target fills
The stock trades up through $4.08 and the resting sell fills. The exit adds liquidity and earns the rebate.
Path BThe stop fills, removing liquidity
The stock drops; the stop at $3.96 triggers and fills at $3.95. A stop becomes a market order, so the exit removes liquidity: a take fee instead of a rebate.
Path CScratch at the bid
The stock goes nowhere. At the time stop the trader sells at $4.00 with a marketable order, removing liquidity again.
Review note: the fees on Path A were $16.56; on Paths B and C, $26.56. Losing and flat trades exit with marketable orders more often, so they tend to pay the take fee twice, while winners resting at a target can earn a rebate on the way out. That asymmetry belongs inside your expectancy. The rest of this lesson covers fee plan types, the regulatory fees and their dates, and a worksheet for your own plan.
Maker-taker in plain terms
Venues compete for resting orders, because resting orders make a market look deep. Under maker-taker pricing they pay a rebate to the order that rests (the maker) and charge a fee to the order that trades against it (the taker). The fee is usually larger than the rebate, and the venue keeps the difference.
- Fee cap. SEC Rule 610(c) caps the fee for accessing a protected quotation at $0.003 per share for stocks priced at $1.00 or more, and at 0.3% of the quotation price below $1.00. In 2024 the SEC adopted a lower cap of $0.001 per share; its compliance date has been deferred to the first business day of November 2027 (SEC Release 34-105656, June 11, 2026). Until then, take fees up to $0.003 per share remain within the cap (as of 2026-10-05).
- Inverted venues. Some venues reverse the model: they pay the taker a small rebate and charge the maker. Routing to them changes the arithmetic.
- Pass-through. Whether you see these fees depends on your plan. Per-share plans often pass exchange fees and rebates through on each fill. Bundled plans include them in the commission.
Rebate economics and route choice are an Advanced course topic, Order routing.
Commission plan types
| Plan type | How it charges | Who it suits on cost alone |
|---|---|---|
| Per share | A rate per share per side, often with a minimum and a maximum per order; exchange fees and rebates passed through | Traders whose size varies; costs scale with shares |
| Per trade | A flat amount per order, exchange fees usually included | Larger orders; expensive for small size |
| Tiered | Per-share rates that fall as monthly volume rises | High-volume traders, once they reach the tiers |
| Commission-free | No stated commission; the broker earns elsewhere, for example from payment for order flow | Check execution quality and order-type limits; costs move into the fill price |
These are descriptions, not recommendations. Fee schedules change; note the date you checked yours.
Regulatory fees on sells
Two fees apply to sales of stock, not purchases. Brokers usually pass them through on each sell.
- SEC Section 31 fee. Charged on the dollar value of covered sales. The rate has been $20.60 per million dollars since 2026-04-04 and remains in effect until 60 days after the SEC's fiscal 2027 appropriation is enacted (SEC fee rate advisory, as of 2026-10-05). On a $10,000 sale that is about $0.21.
- FINRA Trading Activity Fee (TAF). Charged per share sold. FINRA has paused it, setting the rate to $0.00 for trades from 2026-10-01 through 2026-12-31 (SR-FINRA-2026-021). It is scheduled to resume on 2027-01-01 at $0.000195 per share, with a maximum of $9.79 per trade: the 2026 rate, which SR-FINRA-2026-020 keeps in place through 2028-12-31 (as of 2026-10-05). This lesson's examples use the scheduled 2027 rate, because the pause is temporary.
Short sales also carry locate and borrow costs, which can dwarf every fee in this lesson on hard-to-borrow stocks. US Day Trading Fundamentals covers locates and borrow fees as part of short-selling basics. Some brokers also pass through other small per-share charges, such as consolidated audit trail fees; check your statement.
The cost-per-round-trip worksheet
For your own plan, fill in one row per line item, at two sizes you actually trade:
| Line | Entry | Exit | Source and date checked |
|---|---|---|---|
| Commission | per share or per order | per share or per order | plan document |
| Exchange fee or rebate | take or add | take or add | plan's pass-through schedule |
| Section 31 | — | sale value × rate | SEC fee rate advisory |
| FINRA TAF | — | shares × rate, capped | FINRA schedule |
| Other pass-throughs | statement | ||
| Total per round trip | |||
| Break-even move | total ÷ shares, in cents |
Compute it twice: take on entry with an add on exit (a target that fills), and take on both sides (a stop or a scratch). Compare the break-even move with your typical target and your typical spread. If your target is 10 cents and the break-even move is 1.3 cents, costs take 13% of every winner before any slippage. Risk/reward and breakeven win rate turns that into a breakeven win rate.
Observe vs. infer
After a week of trading on Plan P (Illustrative):
| What the statement shows (observed) | What a trader might infer | Why it is not established |
|---|---|---|
| Net rebates of $42 for the week | "I'm getting paid to trade" | Rebates came with commissions and take fees far larger; net costs were still positive |
| Losing trades paid more in fees than winners | "My broker charges more on losers" | Losers more often exit with marketable orders, removing liquidity |
| Regulatory fees on sells only | Regulatory fees apply to sells | Observed; both fees are charged on sales |
| Fees differ between two identical-looking trades | "A billing error" | Different routes and add/remove status change the fee; check the fill details first |
What shifts the odds
These shift your cost per round trip mechanically; they are not FennEdge findings:
- Order type at entry and exit. Marketable orders remove liquidity; resting limits add it, if they fill.
- Fill probability of resting orders. A resting target can miss when price touches it but your place in the queue is not reached. Then the exit is a marketable order: a lower price and a take fee.
- Size relative to plan minimums. Per-trade and minimum-per-order charges weigh most on small orders.
- Price level. Section 31 scales with dollar value; per-share fees do not. A $0.80 stock and a $8.00 stock pay the same per-share commission on very different dollar amounts.
Cost of being wrong
Using the Quarry Pine plan at 2,000 shares on Plan P (Illustrative):
| Situation | Costs | Effect in R |
|---|---|---|
| Target fills as a resting order (add) | $16.56 | −0.21R from a +2.00R gross win |
| Target misses, exit at $4.07 with a marketable order | $26.56 | gross falls to $140; net +1.42R |
| Stop or scratch (take on both sides) | $26.56 | −0.33R on top of the price move |
| Same trade on Plan T at 200 shares | $9.96 | 62% of an 8-cent gross gain |
Underestimating costs by half a cent per share at 2,000 shares understates the cost of every round trip by $10, or 0.13R at this stop.
How many trades before this means anything
Costs are the one part of a scalping process you can know precisely before you trade, so they do not need a large sample. What does need one is the mix of fills: how often your exits add rather than remove liquidity, and how often a resting target misses. That share comes from your own log, and it takes dozens of trades before it is stable. How many trades before your numbers mean anything covers the method.
What this lesson does not claim
- It does not recommend any broker, plan type or venue. Plan P and Plan T are Illustrative.
- Exchange fee and rebate levels here are Illustrative; each exchange publishes its own price list, and the levels change.
- Regulatory rates and dates are as of 2026-10-05 and are scheduled to change. Check the current SEC advisory and FINRA schedule before relying on them.
Go deeper
- FennEdge first.
- If you trade live, the Trading Journal syncs real fills from supported brokers. On Pro and Max (as of 2026-10-05), its Fees page shows commissions and fees as your broker reports them, for a limited set of supported brokers: a quick check of your worksheet against reality. It holds broker-synced trades only, not simulated or practice entries.
- The DAS course lesson Order types and time in force shows how order type and route are set in one platform's scripts, which decides whether a fill adds or removes liquidity.
- Exchange price lists. The Nasdaq price list and NYSE trading information publish current fees and rebates by tier. Note the date you read them.
- Tick size and the access fee cap. The SEC's 2024 amendments tie a lower fee cap to new tick sizes; both compliance dates are deferred to November 2027 (as of 2026-10-05). The Advanced lesson Tick size covers them.
- Commission-free plans. No commission does not mean no cost: execution quality and payment for order flow move the cost into the fill price, which Slippage shows how to measure.
- Related: Marketable limit orders, Scalping vs day trading, and the bid-ask spread and market vs. limit orders lessons in US Day Trading Fundamentals.
Exercises
Seven exercises follow this lesson: three concept checks (adding vs. removing liquidity, which side pays regulatory fees, whether rebates are an edge), three calculations (cost per round trip on a per-share plan, the break-even move on a per-trade plan, and a TAF with its cap) and one practice task. Exercises, answers and progress are available after signing in.
Practice task: fill in your own cost worksheet. Using your broker's current fee schedule, fill in the worksheet above for two sizes you trade, once for a take-and-add round trip and once for take-and-take. Record each source and the date you checked it, then compute the break-even move in cents and compare it with your typical target. This is a worksheet, not a trade log: keep it on your own device and separate from the Trading Journal, which holds only real broker-synced trades. If you log practice trades, carry the result into the fees_usd column of the practice log (column guide).
Primary sources
- US Securities and Exchange Commission. Section 31 fee rate advisory for fiscal year 2026.
- FINRA. SR-FINRA-2026-021: temporary pause of the Trading Activity Fee.
- FINRA. SR-FINRA-2026-020: two-year postponement of scheduled fee increases, keeping the TAF at its 2026 rate through 2028 (Federal Register notice 91 FR 60427, September 23, 2026).
- US Securities and Exchange Commission. Release 34-105656: temporary exemptive relief from Rules 610(c) and 612 compliance dates (June 11, 2026).
- Electronic Code of Federal Regulations. 17 CFR 242.610, access to quotations.
- Nasdaq Trader. Price list: trading.
Sources checked 2026-10-05. Regulatory rates and dates are as of that day. Quarry Pine Energy, both fee plans, the exchange fee and rebate levels, and all prices and outcomes are fictional and Illustrative. This lesson is education, not a recommendation to buy or sell any security or to use any broker. Past patterns do not indicate future results.