Lockdown at Day 18: The Three Days That Decide the Hatch
TL;DR: At day 18: stop turning, raise humidity to 65–75%, close the incubator and leave it closed. That is the whole procedure. The failure mode is almost always the same — a keeper opens the lid to check on the chicks, humidity crashes, the membrane dries onto a chick that has pipped, and it cannot turn to cut its way out. Prepare the brooder before lockdown starts so you have nothing to do for three days except wait.
Everything that has gone right in the first 18 days can be undone in the last three by curiosity.
What Changes at Day 18
| Setting | Days 1–18 | Days 19–21 (lockdown) |
|---|---|---|
| Turning | 3–5 times daily | Stop completely |
| Humidity | ~50–55% | 65–75% |
| Opening the incubator | Brief, for turning and candling | Do not |
| Egg position | Turned, blunt end slightly up | Laid flat, undisturbed |
If you use an automatic turner, switch it off or remove it and lay the eggs flat. Leaving it running is a common and costly oversight.
Why Turning Stops
By day 18 the chick is positioning itself to hatch: head under the wing, beak toward the air cell at the blunt end. From there it will internally pip — break into the air cell and take its first breath — and then externally pip through the shell.
Turning at this stage disrupts that positioning. The job of the last three days is stability, not movement. See egg turning in the incubator for the first 18 days.
Why Humidity Goes Up
Because the chick must cut through the inner shell membrane, and that membrane has to stay soft.
At high humidity the membrane remains pliable and the chick can turn inside the shell, cutting a circle as it goes. As humidity falls, the membrane dries and toughens. A chick that has pipped into a drying membrane becomes glued in place — it cannot rotate, cannot cut, and dies in the shell after doing almost all of the work.
This is why opening the incubator during lockdown is so damaging. The humidity drop is immediate, and the membrane of an already-pipped egg can dry within minutes. See incubator humidity.
Prepare Before You Lock Down
Do all of this on day 18, before the lid closes:
- Top up the water channels to the lockdown level, with warm water.
- Remove or disable the turner, lay the eggs flat.
- Do the final candling if you want one — day 18 is the last practical point. See candling eggs.
- Remove clear eggs and obvious quitters. An egg that rots and bursts during hatch contaminates the whole tray.
- Set up the brooder now. Heat on, tested, bedding down, feed and water ready. See how to brood chicks and brooding temperature for chicks.
- Put a towel or non-slip liner under the eggs if your tray is slippery — newly hatched chicks on a smooth floor can develop splayed legs.
Then close it and leave it alone.
What You Will See, and When
Day 19–20: you may hear cheeping from inside the eggs before anything is visible. This is normal — the chick has internally pipped and is breathing air.
External pip: a small crack or hole in the shell. Then, often, nothing at all for many hours. This is normal. The chick is resting and absorbing the remaining yolk.
Zipping: the chick turns inside the shell, cutting a line around it.
Hatch: the chick pushes the shell apart and emerges wet, exhausted and unimpressive-looking. That is what a healthy newly hatched chick looks like.
Drying: several hours before it is fluffed and steady.
The whole process from external pip to hatch can take many hours, and watching it in real time is agonising precisely because it looks like nothing is happening when everything is.
Should You Ever Help?
Almost never, and never early.
A chick that cannot get out often has an underlying reason — poor position, weakness, a developmental problem. Intervening early causes bleeding, because the blood vessels in the membrane have not yet withdrawn, and a chick that bleeds at this stage usually dies.
If you are considering it after many hours of no progress, understand that you are performing a last-resort procedure with a poor success rate — not a routine assist. The far better use of the same attention is fixing the humidity and temperature settings for the next batch, which is where the actual cause usually lies.
After the Hatch
- Leave chicks in the incubator until dry and fluffed — several hours. A wet chick chills fast.
- Waiting for stragglers is normally safe. A newly hatched chick lives on its absorbed yolk reserves for a substantial period, which is how hatchery chicks survive shipping.
- Move them together once the hatch is finished, into the prepared brooder.
- Clean the incubator thoroughly afterwards. Hatch debris is organic material in a warm humid box — see cleaning and disinfecting a chicken coop for the general principle.
Then read why eggs did not hatch with the unhatched eggs in front of you. That post-mortem is how the next hatch gets better.
The Honest Limits Here
The day-18 lockdown, the stop in turning, the humidity increase and the membrane mechanism behind it are standard incubation practice, consistent with our main incubation guide. This guide deliberately gives no procedure for assisting a hatch: it is a last-resort intervention with a poor success rate and a real risk of causing fatal bleeding, and describing it in step form would encourage exactly the early intervention that kills chicks. Follow your incubator’s manual for model-specific lockdown instructions.
Related: incubator humidity, egg turning, candling eggs, how to brood chicks.
Frequently Asked Questions
What is lockdown in incubation?
The final three days before hatch, from day 18 to day 21. Egg turning stops, humidity is raised to 65-75%, and the incubator is kept closed so conditions stay stable while chicks position, pip and hatch.
Why does turning stop at day 18?
Because the chick is orienting itself to hatch. Continued turning disrupts that positioning at exactly the point where the chick needs to settle into place.
Why raise the humidity for lockdown?
To keep the internal membrane soft enough for the chick to pip through. A membrane that dries out becomes leathery, and a chick that has pipped but cannot progress is usually fighting a dried membrane.
Can I open the incubator during lockdown?
Avoid it. Every opening drops humidity sharply at the exact moment the chicks need it most, and the membrane can dry onto a chick within minutes. If you must open it, do it fast and have everything ready first.
When should I move the chicks out?
Once they are dry and fluffed up, which can take several hours. A wet newly hatched chick chills quickly outside the incubator.
How long can a hatched chick stay in the incubator?
A newly hatched chick can go a substantial time on its absorbed yolk reserves, which is why waiting for stragglers is normally safe. Once the hatch is finished, move them to the brooder where feed and water are available.
Should I help a chick that is struggling to hatch?
Usually no. Hatching takes many hours and looks alarming. A chick that cannot get out often has an underlying problem, and helping too early causes bleeding. Intervening is a last resort, not a first response.