Settle him away from the door before the first knock
The safest Halloween dog is not the one greeting visitors bravely; he is the one who never has to deal with the door at all. Choose a back room away from the hallway, set it up before dusk with his bed, water, a familiar blanket and a long-lasting chew or stuffed toy, and settle him there with the door closed or a gate fitted while the evening is still quiet. Draw curtains against flashing decorations and passing costumes, put on familiar background sound at a normal volume, and check in regularly yourself rather than sending excited children in to visit him. A dog behind the front door, even on a lead, faces a stream of strangers in masks looming, shouting and thrusting sweet tubs toward him, which is a frightening pattern even for a dog who loves people on ordinary walks.
Control the doorway for the humans who stay there
Treat every door opening as an escape opportunity and organise it like one. Keep your dog's room or gate shut before the outer door opens, use a hallway barrier if your layout allows it, and agree that one adult owns the door all evening rather than a rotation of children drifting back and forth. Keep his lead hanging by his quiet room, not by the front door, so nobody is tempted to improvise a greeting. If he must cross the hallway for a toilet break, take him on lead through a side or back exit during a lull, and keep garden gates latched, because a dog startled by a firework or a screaming decoration may bolt from a garden he knows perfectly well. Check his collar fit and ID before dark, on the one night of the year when doors open every few minutes.
Keep sweets, decorations and costumes out of reach
Halloween imports a concentrated set of hazards into the hallway. Keep the sweet bowl on a high surface away from the door, never on the floor between visitors, and clear dropped sweets after each group, since chocolate and sugar-free sweets in particular can seriously harm a dog who hoovers them up in seconds. Keep lit pumpkins with real candles off the floor and away from tails, route decoration cables along walls, and remove any costume your dog is wearing the moment supervision stops, because chewed elastic, plastic and glow accessories end up swallowed by bored dogs. If you dress him up for a photo, keep it brief, loose and supervised, and abandon the idea cheerfully if he freezes, paws at it or tries to chew it off.
If the evening still goes wrong
Call a vet promptly if your dog eats chocolate, sugar-free sweets, raisins from a treat bag, or part of a costume or glow item, and keep the wrapper or remains to show exactly what he took. Do the same if a dog who got to the door snaps from fear, because the bite risk to a child and the stress to your dog both deserve a calm, factual follow-up the next day with your vet or a qualified behaviour professional rather than blame on the night. If he slips past a visitor, search the street, front gardens and parked cars at once, ask neighbours to check sheds, and keep one person at home with a phone in case he circles back. When that first search still leaves him missing, turn to KinsLe: the Lost Pet Alert System sits inside his profile without charge, appears as a map listing, and enables whoever spots him hiding nearby to contact you by direct message.