Trendline

A straight line joining successive swing points to frame a trend.

Most traders meet this term for the first time inside a platform or a fee table rather than in a textbook, which is why the wording used by brokers can be confusing. The practical version is simpler: it describes one specific piece of how a trade is priced, sized, executed or protected, and once you know which of those four it touches you can usually work out the rest.

If you are comparing brokers, the useful question is not what the term means in theory but what number sits behind it at each firm. Our comparison pages publish those numbers side by side so the definition turns into something you can act on.

Terminology only earns its place when it changes a decision. A trader who understands how costs are quoted will read a spread table differently; a trader who understands the protection rules will read a broker's entity disclosure differently. Both save money, and the second can save a great deal more than the first.

The brokers listed below are all FCA authorised and all scored using the same six-factor model: cost, execution, platform, product range, funding and support. Where this term maps to one of those factors, the score already reflects it.