How to Screen Stocks: A Practical Guide

A stock screen is a question you can repeat. “Show me profitable companies whose revenue is still growing” is a question. A pile of twenty loosely related filters is not. The useful habit is to write the question first, turn it into a few rules, and then let the screen run again when the data changes.

Start with the decision

Before you touch a metric, write down what you would do with a name that passes. Are you looking for a business you might study this weekend, or a list you want checked every night? Those are different jobs.

A research list can be a little wider. You still have to read the filings yourself. A nightly watch should be tighter, because every name that enters or leaves the list is something you asked to hear about.

Two questions cover most retail screens:

• Is the business still getting healthier?
• Is the price asking too much for that progress?

You do not need a third theme on day one. Add it later, after you have seen what the first two return.

Use a few filters, and make them specific

A screen fails when every rule is a vibe. “Quality” and “undervalued” are not rules until you name a metric and a threshold. A workable starter screen for established companies looks like this:

• Market cap above a size you are willing to research. Ten billion dollars is a common floor when you want businesses with a filing history. Drop it if you are intentionally hunting smaller companies.
• Revenue growth, year over year, above zero. You are asking whether the top line is larger than it was a year ago, not whether this quarter beat a whisper number.
• Positive free cash flow. Earnings can look fine while cash goes out the door. Cash flow is the harder number to dress up for long.
• A valuation cap you can defend, such as free cash flow yield above a level you would actually accept, or a price-to-earnings ratio below a number you have used before.

That is four rules. If the list comes back empty, loosen one threshold. If it comes back with hundreds of names, tighten one. Do not add a fifth rule just to feel thorough.

You can type that idea in plain language in the StockWatch screener, then switch to the visual builder and edit the thresholds. The screener guide shows both modes. The metrics reference is the list of fields those rules can use.

Ask for the pattern more than once

The latest quarter is the noisiest quarter. A single jump in revenue can be a contract pull-forward, an acquisition, or a comparison against a weak period last year. A screen that only checks the newest point will keep surfacing those.

Require the condition in several recent periods. “Revenue grew year over year in at least 3 of the last 4 quarters” is a different claim from “revenue grew last quarter.” The first one still lets a company have a soft quarter. It refuses companies whose growth is a one-time print.

StockWatch calls this filter At Least X of the Last Y. The consistency guide walks through the fields. A companion article, how to screen for consistent growth, covers when to use it and when a strict streak is too harsh.

Sort for the decision

Filters decide who is allowed on the list. Sort decides who you look at first. If the question is “where is growth holding up,” sort by year-over-year revenue growth. If the question is “what is cheap among businesses that are still growing,” sort by free cash flow yield or by price-to-earnings ratio.

Leave the sort aligned with the decision. A screen sorted by market cap will show you the largest company that scraped through, which is a different list from the one you meant to read.

Save it

A screen you rebuild from memory every Sunday will drift. Save it, give it a name that states the question (“profitable growers”), and let it re-run when new data arrives. On StockWatch a saved screen is a watch. Turn on alerts if you want an email when a company enters or leaves. The alerts guide covers how that notification works.

Then stop adding rules for a while. Run the screen. Open two or three names. Read the filing behind the metric that got them onto the list. If the same kind of false positive shows up three times, that is the next rule. If it does not, the screen is already doing its job.

A second screen, if you want one

Cash is a different question from growth. A second saved screen can look for companies that already generate free cash flow and trade at a yield you find interesting, without demanding rapid revenue growth. That list will include mature businesses the growth screen ignores. Free cash flow yield is the metric to understand before you set the cutoff.

Keep the two screens separate. A single screen that demands high growth and a high cash yield at the same time mostly returns nothing, or it returns special situations you did not mean to hunt.