December means a full house. Relatives fill the hallway, presents pile up by the door, a new toy waits under the tree, and the family dog ends up somewhere he really should not be. When a dog slips out on a night like that, most owners feel a flicker of relief. He is chipped, so he will come back. It is a reasonable thought, and a microchip is one of the best things you can give a dog. But it helps to know what the chip actually does on the night it matters, and what it cannot do for you.

What does a microchip do when your dog gets out?

A chip is a tiny number under the skin. It sits there silently until somebody catches the dog, brings him to a vet or a shelter and runs a scanner over his shoulders. Only then is the number looked up in a chip registry, and someone calls whatever owner contact details happen to be on file. That is the weak point. The record is only as current as the last time you touched it, and for many owners that was adoption day, a move or two ago. When a chipped dog never makes it home, stale contact information is usually the reason. The chip did its job; the phone number on the other end simply rang at an old address or went nowhere at all.

What the shelter study found

Researchers writing in JAVMA in 2009 followed more than 7,700 stray animals through 53 US shelters. Dogs with a microchip went back to their owners 52.2 percent of the time, against 21.9 percent for dogs without one. That gap is exactly why chips are worth it. Flip the figure, though, and close to half of the chipped dogs never got home, mostly because the registry held the wrong details or none at all. A chip leans on paperwork from years ago. A free PawBoost alert leans on nothing but what you do in the minutes after the dog vanishes, and that is the part the chip leaves open.

Which website should you use to report a lost dog?

Think of it as two separate jobs. On a quiet afternoon, log in to your chip registry and make sure the phone number and address are right; that is a registry task and has nothing to do with the alert. On the night itself, head to www.pawboost.com and post a free alert before anything else. That one report on PawBoost reaches people in your zip code the same evening, through the local Facebook page, the email subscribers and nearby app members. After that, search the PawBoost lost and found listings for your zip code in case a neighbor has already picked your dog up.

The part of the outcome you control

A chip is a safety net that only catches once your dog is in someone’s hands and under a scanner. Everything before that moment is up to you, and a free PawBoost alert sent the minute he goes missing is the half of the outcome an owner actually gets to steer.