Usually not
Short answer: Usually not in a rented dumpster. Major dumpster programs ban creosote-treated ties and poles.
Bagster lists railroad ties as unacceptable, and Dumpsters.com says railroad ties and telephone poles aren't allowed. EPA says creosote-treated wood can usually go out as ordinary household trash, so a local landfill may accept it directly.
Call your county landfill (many take them separately for a fee) or a landscape materials yard. Don't burn them.
Checked October 2026. Rules change; your hauler's prohibited-items list is the final word.