Normal body temperatures vary, but if your temperature is 96°F and you feel sick, there might be something else going on.

You may feel ill and take your temperature, assuming you have a fever. Instead, your thermometer reads 96°F (35.55°C).

This lower-than-average temperature could occur for several reasons, including an underactive thyroid, low blood sugar, circulation issues, vitamin deficiency, medication, or, more rarely, sepsis.

Understanding body temperature is important to making sense of your 96°F reading. A temperature of 98.6°F (37°C) is considered a “normal” temperature. However, studies suggest “normal” may vary from 97°F (36.1°C) to 99°F (37.2°C).

Typical temperature readings may vary depending on your age and the method you use to measure it.

Incorrect temperature readings could factor into why your thermometer reads 96°F (35.55°C).

To make sure you measure accurately, follow these guidelines:

  • Follow the manufacturer’s instructions for your thermometer.
  • Consider any factors that could have led to an inaccurate temperature. An oral reading may be affected if you’ve sipped a cold drink or kept your mouth open while taking your temperature. An armpit reading may be lower if you did not hold the thermometer in the correct place or if you improperly closed your arm.
  • Take your temperature a few times to make sure the reading is correct.

If you’ve taken your temperature according to instructions, it’s possible your low temperature and symptoms are due to a condition.

Hypothyroidism occurs when your thyroid is not functioning properly. Hypothyroidism means your thyroid is underactive and does not produce enough thyroid hormone for your body.

Along with a lower body temperature, you may experience:

Hypothermia occurs when your body is at 95°F (35°C) or lower. Hypothermia is a very serious medical condition that can be fatal if not treated immediately by medical professionals.

This condition can occur due to exposure to cold weather, submersion in cold water, prolonged time in cold, wet clothes, or a cold home environment. An early symptom of hypothermia is shivering.

Hypothermia requires immediate medical attention, so call for emergency help if you suspect you have hypothermia.

If you have to wait for medical help, try to warm yourself up with blankets or a hot drink.

A drop in body temperature could be a symptom of sepsis. This occurs when your body starts attacking itself instead of an infection. It can damage your tissues, shut down your organs, and even lead to death. Other symptoms of sepsis include:

  • signs of infection
  • changes in mental state
  • feeling very sick, such as having a hard time breathing or feeling pain

Seek immediate medical help if you think you might have sepsis.

Other factors that can cause a lower temperature include:

  • Older age: You may have a lower body temperature as you get older. You may have less body fat in your arms and legs, dry skin, and a slowed metabolism as you get older. These can all contribute to a lower body temperature as heat can escape more easily.
  • Medications: Certain medications may lower your temperature. These include beta-blockers and some antipsychotics.
  • Exposure to cold temperatures: Your temperature may be low if you’ve been outside in cold weather. Wear warm enough clothes and keep your head covered in cold weather. Avoid getting wet in cold weather.

It’s important to consider your typical baseline to determine whether the temperature reading is unusual for you.

Call a healthcare professional if your temperature is 96°F (35.55°C) and you feel unwell or if you have concerns about your low temperature. You can describe your symptoms over the phone. A doctor may offer a diagnosis or ask you to make an office visit.

You need immediate medical treatment if your temperature drops due to hypothermia or sepsis. Seek care if you have a low temperature along with:

  • breathing difficulty
  • slowed speech
  • confusion or other mental changes
  • tiredness
  • blue skin or lips

Infants with a low body temperature should be seen by a doctor immediately. Other symptoms of hypothermia in infants include red or discolored and cold skin, sleepiness, and disinterest in feeding.

There may be several reasons you feel ill and have a thermometer reading of 96°F (35.55°C).

You may have taken your temperature incorrectly. Or you may have another factor contributing to the lower temperature, like advanced age, medication use, or hypothyroidism.

Rarely, you may have a serious illness like hypothermia or sepsis that requires immediate attention. Speak with your doctor if you feel unwell and have a low temperature.