Costs vs day trading
Lesson 3 · about 9 min
Every trade pays a toll: the bid-ask spread, commissions where they exist, slippage on entries and exits, and the occasional bad fill. The toll is roughly fixed per trade, but the profit you are trying to capture scales with how far price moves during the hold. That single relationship is why swing trading is easier to make work than day trading for most people, and it deserves to be seen in numbers.
The toll per trade
Assume a liquid US stock at $50 with a $0.02 spread, zero commission, and $0.01 average slippage on each side.
| Cost component | Per share, round trip |
|---|---|
| Half spread, entry | $0.01 |
| Half spread, exit | $0.01 |
| Slippage, entry | $0.01 |
| Slippage, exit | $0.01 |
| Total | $0.04 |
$0.04 on a $50 stock is 0.08%. That sounds like nothing. It is not nothing; it is nothing relative to a target, and targets are where the two styles diverge.
Cost as a fraction of what you are trying to make
A day trader targeting a $0.40 move on that stock pays $0.04 to attempt it: 10% of the target, before being wrong about direction at all. A swing trader targeting a $4.00 move pays the same $0.04: 1% of the target.
| Style | Target move | Round-trip cost | Cost as % of target | Trades per year | Annual cost on 100 shares |
|---|---|---|---|---|---|
| Day trading | $0.40 | $0.04 | 10% | 1,000 | $4,000 |
| Swing | $4.00 | $0.04 | 1% | 60 | $240 |
Now put that into expectancy. Suppose both traders have exactly the same skill: they are right 50% of the time and their winners are twice their losers. Before costs, that is a healthy edge for both. After costs, the day trader has surrendered a tenth of every winner and added a tenth to every loser, and needs to be noticeably better than the swing trader just to end up equal.
In futures, forex and crypto the same logic holds with different numbers. Perpetual crypto contracts charge taker fees per side plus funding every eight hours; a swing trade pays the funding for longer but pays the taker fee a fraction as often. In forex, the spread on a major pair is a few tenths of a pip, which is trivial against a 150-pip swing target and material against a 10-pip scalp.
The costs nobody puts on the statement
- Pattern day trader rules. In the US, a margin account under $25,000 that makes four or more day trades in five business days gets restricted. Swing trades do not count. A small account can swing trade freely and cannot day trade freely.
- Data and tools. Serious day trading needs real-time Level 2, fast execution and often paid data feeds. Swing trading needs end-of-day data, which is free or close to it.
- Attention. The lesson on time already covered this. It is a cost, and it compounds into worse decisions.
- Taxes. In most jurisdictions all short-term trading is taxed the same, but a swing trader with 60 trades has 60 lines to reconcile; a day trader with 1,000 has 1,000.
What day trading has that swing trading does not
Be fair to the other side. Day trading has no overnight gap risk, gives faster feedback on whether a method works, and allows more trades per unit of time, which means an edge (if it exists) compounds faster. Those are real advantages. They belong to traders who have the hours, the capital above the regulatory floor, and a demonstrated edge on the short timeframe.
For someone with a job, an account under a few hundred thousand and no track record yet, the arithmetic of costs points the other way, and it points there hard.
Key idea: Trading costs are roughly fixed per trade while profits scale with the size of the move you hold for. Longer holds make the same skill worth more.
The consequence for how you trade
Since each trade costs about the same regardless of how long you hold, the swing trader's job is to make sure each trade is worth the toll. That means:
- Only taking setups whose target is at least 2R away, so the fixed cost is a small fraction of the goal.
- Not trading tiny moves on the daily chart just because a signal appeared.
- Not churning: exiting a good trade on Tuesday and re-entering the same idea on Thursday pays two tolls for one move.
Try it: Pull up your broker's statement or fee schedule. Compute your round-trip cost per share or contract, including a realistic slippage estimate. Then divide that cost by the target of your last five trades. Any trade where the cost was more than 5% of the target was a trade that needed a better setup or a longer hold.
Recap
- Round-trip cost per trade is roughly fixed: spread, slippage, and any commission or fee.
- The cost matters as a percentage of the target; swing targets are ten times larger, so the toll is ten times less significant.
- Frequency multiplies the toll: 1,000 trades a year pays 1,000 tolls.
- Day trading also carries regulatory floors, data costs and attention costs that swing trading avoids.
- Take only trades whose target is at least 2R away and do not churn in and out of the same idea.
See it drawn
Original diagrams for the ideas on this page. Illustrative, not real market data.