A subheading is a mini-headline or text that is found under the main headline to give further insight or support for the headline. Headlines are used to entertain, add shock, or hook readers to make them want to know more, but the subheading guides the reader to keep reading or scanning the information.
A subhead is also designed to keep their attention. It can talk about the benefits someone will gain from the product or service. It can also further explain the headline. Most of all, a subheading will encourage readers to act.
A good subheading shows personality and creates curiosity. They should be useful and unique. Short subheads are best. The very first one should be the most engaging. Subheads should be used throughout the content to keep it scannable and readable. Subheads should keep things moving in a parallel structure. The length should also be similar. The best practice for effectiveness is to keep them at 70 characters or less within the content. Additionally, the subhead should keep things moving forward.
As a rule of thumb, when using subheadings, use just enough persuasion to keep them interested while telling them just enough. Subheads directly under the headline should be 10 to 30 words at the max. Most subheads are twice the length of the main headline.