Why Are My Chicken Eggs Not Hatching? (5 reasons with solutions)

Hatching chicken eggs at home is not only a great way to increase the size of your flock, but can also be incredibly rewarding and educational for kids.  The process of watching those little eggs sit in the incubator for 21 days before a small, fluffy chick pushes its way out never gets boring. 

I have lost count of the number of chicks we have hatched and raised at home. However, the process can be incredibly frustrating when few or none of the eggs actually hatch.

There can be a number of reasons chicken eggs fail to hatch, and these include;

  • Eggs were not properly fertilized
  • Temperature fluctuations in the incubator
  • Humidity fluctuations in the incubator
  • Improper storage of the eggs prior to incubating
  • Good old-fashioned bad luck!

Eggs Were Not Properly Fertilized

Sometimes when we keep either a young or an old rooster with our hens, then don’t fertilize the girls properly.  Young roosters are often inexperienced and may try to service too many hens in one go.  Older roosters might not have as much ‘get up and go’ as they used to, so the eggs don’t actually get fertilized.

There is one sure-fire way to check your eggs are fertile without having to wait the full 21 days to see if they hatch, and that is by candling the eggs. Candling the eggs is the term used for shining a torch through the eggs after it has been in the incubator for a few days.  If the egg is fertile, you will see veins beginning to form inside the egg. 

If you see nothing but the egg yolk inside, the egg wasn’t fertile and it will never develop into a chick.

How to candle a chicken egg

Candling a chicken egg is a fairly straightforward process.  

  1. Make the room the incubator is in as dark as possible. The darker the room the easier it will be to see inside the egg.
  2. Carefully remove the eggs from the incubator one at a time and hold them just above a torch that is switched on.
  3. If the egg is fertile you will see veins, or the beginnings of a chick, depending on how long the eggs have been in the incubator.
  4. Replace each fertile egg carefully back into the incubator.
  5. Discard any eggs which are not fertile.  They won’t ever develop, so they may as well be thrown in the compost pile.

Temperature Fluctuations In The Incubator

Chicken eggs are very specific above the ambient temperature whilst they are in the incubator.  The incubator must keep the eggs at a temperature of 100.5°F (38°C).  

Although the eggs can stand a drop in temperature for short periods, which would happen in nature if the mother hen got off the nest to drink some water. If the temperature is too low for a prolonged period of time, the eggs will stop developing and the embryo inside will die.

I used to keep my incubator in the garage until one year, we had a real cold snap and the incubator could not maintain the temperature that one night.  A few days later it became apparent all the embryos had died and not one egg hatched.

To prevent temperature fluctuations inside the incubator, don’t put it anywhere that might be subject to cold weather, and resist the temptation to open the incubator too often.  Every time you open the incubator, the temperature drops sharply.

Humidity Fluctuations In The Incubator

Much like with the temperature inside the incubator, the humidity has to be kept within fairly tight parameters.  

If the humidity is too low, the developing embryos won’t have access to enough moisture and they will stop developing.  Equally, if the humidity is too high the eggs may develop mold which may also lead to the embryos dying off.

The ideal humidity range is 70% to 75% relative humidity.  The vast majority of modern chicken egg incubators will have a small reservoir of water and they will regulate their own humidity levels. 

I have found it prudent to fit a separate digital humidity monitor to allow me to manually check the humidity on a regular basis.

Be aware, that every time you open your chicken incubator the humidity will drop quickly.  If you open the door on a regular basis, the humidity levels will yo-yo up and down and the embryos may suffer.

Improper Storage Of Eggs Before Incubating

A lot of people don’t realize that you can store fertile eggs for about a week before putting them in the incubator.  When you think about it, the mother hen will take 5 to 7 days to lay a clutch of half a dozen eggs before she starts to sit on them.

The problem is, if the eggs aren’t stored correctly in the days before incubation, there is a good chance they will not develop successfully.

To store your eggs correctly before incubation, follow these simple steps.

  1. Store the eggs in a clean egg carton, with the eggs being placed pointy end down.  If the eggs are kept round side down for long periods there is a risk the air sack will become dislodged and the embryo will not develop.
  2. Turn the eggs regularly.  The eggs should be rotated 2 to 3 times a day to prevent the yolk from sticking to the lining of the egg.
  3. Keep the eggs cool and dry.  If the eggs get too warm, the embryo will quickly start to develop.  Keeping the eggs about 40°F to 50°F (5°C to 10°C) is ideal.
  4. Get the eggs into the incubator as soon as possible.  Although the eggs will store for a few days, the longer the time between the hen laying them and them going into the incubator the lower the chances of the embryos developing.

Just Bad Luck!

I can tell you from bitter personal experience, sometimes you will just be unlucky.  There have been instances in the past when I have had eggs fathered by a very fertile rooster, from productive hens and the eggs have been incubated in an expensive hi-tech incubator, but only 3 of 48 eggs hatch.

Sometimes it is just the way it goes.  All you can do is chalk it down to experience and get ready to go again.

My Final Thoughts On ‘Why Are My Chicken Eggs Not Hatching?’

Hatching eggs at home can be rewarding, but can also be a challenge.  As someone that has done it countless times over the last 20 years, I can tell you from first-hand experience that sometimes it goes well and sometimes it doesn’t.  

All we can do is try to get everything right and set all the equipment up properly to give the unborn chicks the best possible chance of developing, and hatching.

Aaron Homewood

Aaron Homewood is HomesteadSavvy.com‘s poultry editor. Arron has spent over 20 years keeping, breeding, and showing different poultry breeds, including chickens, ducks, geese, and quail.​
Poultry Editor