The door opens for a parcel and your dog squeezes past your leg. The street does not wait for training to catch up. Before teaching a cue, change the setup: put your dog in another room or behind a secure gate every time an outside door opens. Make sure everyone in the household knows the routine.
Check that gates latch, garden exits are secure, and your dog's identification details are current. If they have already escaped, use local lost-pet resources promptly and avoid chasing them into traffic. If bolting follows fireworks, visitors, or being left alone, that context matters, a dog trying to flee fear needs more than a sit at the door.
Practice with a safe second layer
Use an inside door or a quiet entrance first. With your dog on a secure lead, reward them for remaining with you as you touch the handle. Open the door a crack, reward if they can stay relaxed. Close it and repeat. If they lunge forward, make the step easier. The door opening can eventually become a cue to wait, but don't make the street-facing door your first test.
Keep a gate or closed internal door as backup during real arrivals, even after practice starts going well. Teach recall separately in a safe area, rewarding the dog well for returning, it is an extra layer, not permission to risk an escape.
If your dog has broken through barriers, repeatedly escaped, or seems panicked, ask your veterinarian and a qualified, reward-based behavior professional for an individual plan. The best success today is unglamorous: the parcel arrives, the outside door closes, and your dog is still safely inside. Once the physical doorway is secured, the escape-prevention guide can help you build a longer prevention plan, a recall cue is not a substitute for a barrier
Sources: Dogs Trust: How to stop your dog escaping or running away. Dogs Trust: How to train your dog to be patient in doorways.