CTO may refer to:
- Chief Technology Officer, an executive-level position in a company or other entity whose occupant is focused on scientific and technological issues within an organization
- Cancelled-to-order, a postage-stamp cancelled by the postal administration before sale to stamp-collectors
- Configure-to-order, in business, the ability of a user to configure a product before ordering
- Control Tower Operator, an aviation term for certain personnel working in a control tower