Support and Resistance (S/R)

Reviewed 11 August 2026 · Sourced from Edwards and Magee, the SEC and our own TA course

What support and resistance actually describe

You pull up a chart. Price has run to roughly the same area three times this year and turned back every time. Later it falls, steadies, and bounces off the low it bounced off two quarters ago. Price keeps stopping in the same two neighborhoods, and nothing on the chart says why.

Those neighborhoods have names. Resistance is the area above the current price where advances keep stalling. Support is the area below where declines keep finding a floor. The words describe a pattern, not a force. Nothing physically holds price anywhere. What is there is order flow: at some prices enough people want to sell that buyers cannot clear them all, so the advance stops; at others sellers run out of anyone to sell into, so the decline stops.

Edwards and Magee gave the concept its standard treatment in Technical Analysis of Stock Trends, chapter 13. Their definitions run on demand and supply: support is buying interest, actual or waiting, heavy enough to stop a decline for a meaningful stretch; resistance is selling interest heavy enough to satisfy every bid and stall an advance. Those are paraphrases. Every copy of the exact wording we could reach was secondary, so it is not in quote marks here.

Settle one thing before the rest. This is not a regulated or standardized term, and no SEC, FINRA or CFTC publication defines it or sets a threshold for any part of it. The SEC’s own day trading glossary entry does not mention technical analysis, charts or chart levels at all. What it does say is that day trading is extremely risky and can result in substantial financial losses in a very short period of time.

Where the idea came from

Most trading ideas have murky parentage. This one does not. Edwards and Magee first wrote Technical Analysis of Stock Trends in 1948 and it never went out of print: an 11th edition appeared in 2019 from Routledge, with W.H.C. Bassetti as third author. An earlier printing, catalogued by the Internet Archive, came out of Springfield, Massachusetts in 1958. Support and resistance is chapter 13, with a second, applied treatment at chapter 30, “Use of Support and Resistance.”

The publisher’s chapter record confirms the chapter and its run of figures, 13.1 through 13.12. More usefully, the book’s own table of contents gives chapter 13 the line “Definition of Support and Resistance Levels — How They Reverse Their Roles.” That settles something people argue about. Role reversal — a broken level flipping to act as the opposite — is not a modern refinement. It was in the original chapter heading.

What the book’s age establishes is that the concept is old, widely taught and consistently described. Not that it works. Nobody had to file it with anyone.

Why they are zones and not lines

You draw a horizontal line at the exact high, call it resistance, and price turns under it once and pokes through it the next time. The line was not wrong. The expectation was.

Selling interest does not sit at one price. It spreads across a small range, because the people holding it decided at different moments and rounded differently. Some placed orders at whole numbers. Some are working an order in pieces. Some are not orders yet — they are intentions that become orders when price gets close. Add intraday spikes that print a price almost nobody traded at, and the edge of a level is genuinely fuzzy.

Our Technical Analysis course teaches these as zones a few percent wide rather than exact prices, and the hedge is doing real work: no standard-setting body publishes a zone width. Treat “a few percent” as an order-of-magnitude caution, not a measurement, and be wary of any source handing you a precise figure.

The cost is concrete: treat a level as an exact price and ordinary noise shakes you out of trades that were fine.

When a broken level changes sides

Price grinds against the same ceiling for months, clears it, runs, then pulls back — and stops almost exactly where the ceiling used to be.

The mechanism is a story about who is left holding what. The sellers parked at that price have been filled, so their supply is gone. Buyers who got in on the break have a reason to defend what they paid. And people who sold near the old ceiling, then watched it break above them, treat a return to it as a second chance. Three groups, all with a reason to buy in the same area. The old ceiling becomes a floor.

It runs in reverse when support gives way: the buyers who defended it are underwater, and many sell into a bounce back to their entry, so the old floor acts as a ceiling. It is a clean story and it does happen. A clean story is not a hit rate. No primary study of how often role reversal holds was reachable for this page, so none is claimed.

How a level gets drawn, and what that proves

The mechanics take a sentence: find two places where price reversed at about the same value, and draw a band through them. Two is the minimum because a horizontal line needs two points. That is geometry, not evidence.

From there, convention takes over. The standard claim is that the more times price has respected a level, and the more volume that traded there, the more significant it is. Nearly everyone teaches it. It has no primary authority behind it — the clearest statement we could reach is a 1999 article in Technical Analysis of Stocks & Commodities, which is secondary, and the academic support is mixed. Treat it as the working assumption of a craft, not a finding.

Trendlines get treated as sloped versions of the same thing and carry the same conventions: two lows to draw one, a third touch before most traders take it seriously. The third-touch figure has no primary source either.

There is a trap under all of it. Every chart has prices it visited more than once; move the line far enough and you can find support anywhere. Drawing a level after the fact and being impressed by how well it worked is memory, not analysis.

What a breakout is supposed to confirm

A breakout is price closing decisively through a level it had been respecting, and most classic chart patterns are support and resistance wearing a shape. A double top is resistance tested twice; a triple top, three times. An ascending triangle is a flat resistance line with higher lows pressing into it, a fixed wall of supply being absorbed. A descending triangle is the mirror: a defended floor with lower highs grinding into it. When the last seller at a fixed price is taken out, the next buyer may have to bid meaningfully higher to find any shares — which is what produces a breakaway gap.

Confirmation matters because of the failure case. Price punches through, looks convincing, and snaps back into the old range. That is a whipsaw, and it is why waiting for a genuine closing break with a few sessions of follow-through is standard practice.

Volume is the usual second opinion, because it is an independent data series — it cannot be shaped the way an outline can. A break on heavy volume carries more weight than the same shape on thin volume. You will also see a number attached: that a credible breakout comes on volume of roughly 1.5 to 2 times average daily volume. That is a rough rule of thumb many traders use, though no exchange or standard-setting body publishes that threshold.

Stage 3 of the Technical Analysis course works all of this on real charts, and Markets · Technical shows levels forming live.

Stops, and what a stop order actually does

The most common practical use of a support level has nothing to do with prediction. It is a place to admit you were wrong: buy near support, put a stop below it, and the level sizes the loss instead of the hope.

That only works if you know what the order does when it fires — the one part of this page with an unambiguous primary source. The SEC’s Office of Investor Education and Advocacy Investor Bulletin on stop, stop-limit and trailing stop orders sets out four things.

• A stop order becomes a market order the moment the stop price is reached.
• The stop price is not the guaranteed execution price. It is a trigger, not a promise.
• In a fast-moving market, the execution price can deviate significantly from the stop price.
• A stop can be triggered by a short-term intraday move, at a price substantially worse than where the stock closes that day.

Put that next to the fuzziness of a level and the tension is obvious. A stop right at the line sits inside the noise. Move it out and the loss you accepted gets bigger. No setting solves both, so it is a trade-off to make on purpose.

What is confirmed and what is convention

Twelve claims about this term were checked for this page. Six held up against a source that can be named. Six did not. Here is the ledger.

None of that makes the concept useless. It organizes a chart into places where something has happened before. It does mean the specifics deserve less confidence than the tone they arrive in. If someone hands you a number here, ask who published it.

What trips people up

• Treating a level as a price instead of an area. The exact high is one print. The interest sits in the area around it.
• Drawing the line after the move. If it was not drawable before the reversal, it did not predict the reversal.
• Counting touches as proof. Two touches is what a line needs to exist. A drafting minimum, not a signal.
• Taking the volume multiple as a test. It is a rough rule of thumb many traders use, though no exchange or standard-setting body publishes that threshold.
• Acting on an intraday poke. A wick through a level and a close through a level are different events.
• Assuming a stop caps the loss. It sets a trigger. The fill is whatever the market is paying at that moment.
• Confusing an old idea with a proven one. Eighty years of teaching is evidence about teaching.

The figures on this page are checked against the source that publishes them, and dated. Published rates move after the release named above — the linked source always carries the current number. This page explains a term; it does not recommend a product.