How does breadcrumb structure affect click-through rate?

Short answer: Breadcrumbs affect click-through rate on two surfaces: in search results they replace a raw URL with an understandable path and make the result more trustworthy; on the site they ease movement to parent categories and deepen exploration.

Where the effect operates

• SERP display: BreadcrumbList structured data shows the site hierarchy in the result line; the user knows in advance where the click leads.
• Trust signal: an orderly hierarchy looks tidier than long, parameter-heavy URLs.
• On-site behavior: breadcrumbs do not strand visitors on a single page; they lead into category exploration.
• Mobile benefit: on a narrow screen a short path reads better than a long URL.

The effect cannot be promised as a fixed ratio; the correct method is measurement. TYS Digital Performance evaluates breadcrumb changes by comparing click-through rate before and after for the same query set in Search Console; the difference is reported against the baseline, and the decision follows that data.