When should a chapter end?

The last line or lines should have some reason for being there. They can:

• be suspenseful ("What are you doing here?")
• be funny ("Tinkerty-tonk," I said, and I meant it to sting.)
• close a scene (She slammed the door behind her, hard enough to make the glass rattle in the windowpanes.)
• bring resolution to an arc of any size (He held John's eyes for a long moment, then leaned over and kissed him full on the mouth.)

but don't end mid-thought or mid-scene arbitrarily.

Follow the standard plot arc: conflict, rising action, and resolution. This is often used to describe plots across a whole novel, but it is equally applicable to a single scene. Each scene needs a conflict of some kind, and the action in that scene will flow from this conflict. When the conflict is resolved (temporarily or permanently), the scene is over.

There is often only a single scene per chapter, but you might put several scenes in the same chapter if they are closely related, or if they illustrate some larger arc of conflict and resolution.

Alternately, some authors choose to end a chapter right before the resolution. When done well, this can add suspense and keep the reader flipping pages.

I would say at the point where you estimate your reader will get to the full stop, curse your name, curse your family's name, swear under their breath and, wearily ignoring the clock telling them they have to be up in four and a half hours for work, mumble: "Go on then, just one more chapter." before looking across to the beginning of the next chapter.

When deciding when to end a chapter, consider the narrative momentum and the emotional impact on your reader. A good rule of thumb is to end a chapter on a note that leaves the reader with a lasting impression, whether it's a cliffhanger, a moment of revelation, or a poignant reflection. Think of chapter endings as emotional bookends that frame the reader's experience. You want to create a sense of closure, but not so much that it feels like a full stop. Instead, aim for a soft landing that leaves the reader wanting more. For example, you might end a chapter on a character's realization, but not necessarily on the resolution of the conflict. This creates a sense of tension and anticipation, drawing the reader into the next chapter. Alternatively, you could end a chapter on a moment of introspection, where the character is grappling with their emotions or thoughts. This can create a sense of intimacy and connection with the reader, making them more invested in the character's journey. In terms of specific techniques, you can use chapter endings to: Raise questions about the character's motivations or backstory Introduce a new plot thread or conflict Create a sense of foreshadowing or ominous tension Highlight a character's emotional growth or change Leave the reader with a haunting image or memory Ultimately, the key is to find a balance between closure and anticipation. You want to give the reader a sense of satisfaction, but also leave them eager to see what happens next.