SOXL vs SOXS

The one-line difference

SOXL is a 3x long semiconductor ETF: it aims to deliver three times the daily return of a semiconductor index. SOXS is the 3x inverse of the same index: it aims to deliver three times the opposite of that daily return. If the semis index is up 1% on the day, SOXL targets roughly +3% and SOXS targets roughly −3%. If the index falls 1%, the signs flip. They are two leveraged bets on the same underlying — one that the chip sector rises, one that it falls — and both reset their leverage every single day.

Same index, opposite leverage

Both funds track the same basket of large semiconductor companies, just with opposite signs and the same 3x multiplier. That symmetry is the whole point: a trader who is bullish on chips can express it through SOXL, and a trader who wants downside exposure can use SOXS without short-selling or options. Because the underlying is one of the most volatile corners of the equity market, the 3x layer makes both funds move violently in dollar terms — a routine day in the index becomes a large day in either ETF.

Note the symmetry in that table is a target, not a promise. Tracking error, fees, and overnight gaps mean a ~10% index move is roughly a ~30% ETF move before those frictions, not exactly. The further you stray from a single day, the looser the 3x relationship gets.

Daily reset: why a ~10% index move is roughly a ~30% ETF move

The "3x" in both tickers describes one day. A leveraged ETF promises a multiple of the day's move, then rebalances overnight so it can promise the same multiple again tomorrow. Within a single session that math is clean: a ~10% move in the index implies roughly a ~30% move in the ETF, before gaps and slippage. The trouble starts the moment you hold across more than one day, because each day's reset compounds against the next.

This is exactly the mechanism that drives leveraged-ETF decay — and it hits SOXL and SOXS the same way, regardless of direction. A flat-but-choppy week can leave both the long and the inverse fund lower than where they started. The detailed compounding math, with a worked two-day example, lives in that companion piece; the takeaway for this page is simpler.

Multi-day decay and path dependence

Because leverage resets daily, your result depends not just on where the index ends up but on the path it took to get there. A smooth one-direction trend can let the compounding work in your favor and amplify a move; a violent, range-bound chop erodes value even if the index is net flat. This is called path dependence, and it is unavoidable in a daily-reset product.

The practical consequence: holding either SOXL or SOXS as a passive "set it and forget it" position is the misuse case that generates most of the horror stories. The issuers say as much in their own prospectuses — these are tactical, short-duration tools meant for traders who actively monitor and manage positions, not buy-and-hold investors.

Gap risk cuts both ways

Leverage magnifies every gap. If the semis index gaps 10% before you can react, a 3x ETF gaps roughly 30% — before any slippage. A protective stop is an instruction to sell once a price is touched; it does not guarantee that price, and in a gap the market can open well past your stop and fill you far lower. That risk applies to SOXL on a down-gap and to SOXS on an up-gap. With 3x leverage on a high-volatility sector, an ordinary overnight surprise can leave a much wider wound than the same news would on an unleveraged stock.

Why holding the inverse overnight is especially risky

SOXS deserves a sharper warning than its long sibling. Over the long run, equity indices have a structural upward drift, and the semiconductor sector in particular has trended higher across most multi-year windows. A 3x inverse fund fights that drift and pays the daily-reset decay tax, so SOXS tends to grind lower the longer it is held — even before a single bad gap. Combine that with the fact that bullish surprises (earnings beats, sector rallies) gap against the inverse fund, and overnight inverse exposure stacks two penalties at once: structural drift and gap risk. That is why a disciplined short-side approach treats the inverse as an intraday instrument and closes it before the close, rather than carrying it into the next session.

Why a rules engine might trade the long in uptrends and the inverse intraday in downtrends

This is the lens behind how Coil works — not a recommendation to trade these instruments, just an explanation of one disciplined approach to a hard pair. Coil is rules-based trading software you run yourself, on your own machine, broker, and capital. Because the long and the inverse track the same index with opposite signs, a single strategy can lean on whichever side matches the current tape:

• SOXL in a confirmed uptrend. When the higher-timeframe trend is up, the rules look to ride a directional move in the long fund and exit, rather than marry it across weeks of chop where decay does its damage.
• SOXS intraday only in a downtrend. When the tape rolls over, the rules can use the inverse for short-side exposure — but never hold it overnight, precisely because of the structural drift and gap risk above.
• Standing down counts. On confirmed sustained-bear days the rules move to cash rather than fight the tape. In a cold 2022 backtest this changed the result from −3.6% to −1.4% — backtested, best-case, one 250-session sample, not a prediction and not a client return. Idle cash can earn the broker's own variable cash sweep (~3.35% APY on Robinhood Gold as of early 2026 — the broker's yield, variable, not paid by Coil, and not risk-free).

Those figures are hypotheses on a small sample — fewer than 500 trades total across all windows tested, on a single ETF pair, about 115 trades a year — not proof, and forward results matter more. To put names to the jargon, the trading-bot glossary defines daily reset, decay, drawdown, and profit factor. If you want to weigh tooling approaches, see Coil vs. trading bots and signal services. None of this makes leveraged ETFs "safe."