| Acronym | Definition |
|---|
| PTO | Parent-Teacher Organization (variant of Parent-Teacher Association) |
| PTO | Paid Time Off |
| PTO | Patent & Trademark Office |
| PTO | Power Take-Off |
| PTO | Pátio (Portuguese postal usage) |
| PTO | Personal Time Off |
| PTO | Phantom of the Opera |
| PTO | Pacific Theater of Operations |
| PTO | Permit to Operate |
| PTO | Police Training Officer |
| PTO | Public Telecommunications Operator |
| PTO | Please Turn Over |
| PTO | Pre-Trial Order |
| PTO | Person Trade-Off |
| PTO | Permeability Tuned Oscillator |
| PTO | Public Telephone Operator |
| PTO | Pick to Order |
| PTO | Powertrain Operations |
| PTO | Professional Try-Out (professional sports) |
| PTO | Paltamo (Railway Station Code) |
| PTO | Public Tender Offer |
| PTO | Prison Talk Online |
| PTO | Push to Operate |
| PTO | Prontuario Terapeutico Ospedaliero (Italy) |
| PTO | Programming and Training Officer |
| PTO | Part-Time Officer |
| PTO | Presentation Text Object |
| PTO | Pure Trust Organization |
| PTO | Preliminary Technical Order |
| PTO | Participating Test Organization |
| PTO | Power Transmission Overdrive |
| PTO | Professional and Technology Officer |
| PTO | Poetry Today Online |
| PTO | Privilege Ticket Order (Indian Railways) |
| PTO | Ping Time Out |
| PTO | Payment, Treatment or Operations (protected health information can only be shared for PTO purposes) |
| PTO | Percent Time Operable |
| PTO | Peacetime Training Objective (US Air Force) |
| PTO | Pakistan Trade Office |
| PTO | Page Turn Over (musical term) |
| PTO | Primary Test Organization |
| PTO | Post-Transient Operation |
| PTO | Planting Thought Organics (Los Angeles, California) |
| PTO | Process Time Observation |
| PTO | Pallet Truck Operator |
| PTO | Property Tax Oversight (Florida) |
| PTO | Polish Tourist Organisation |
| PTO | Personal Trainer One (software) |
| PTO | Public Trust Office (various locations) |
| PTO | Prisoner Transfer Order (US Corrections) |