Meditation has been linked to a decrease in total sleep time for long-term meditators compared to those who do not meditate. This is often seen during intensive meditation practices, such as multi-day silent retreats. Buddhist texts suggest that competent meditators sleep about 4 hours a night. Although meditation is not a substitute for sleep, it can help you sleep better.
It can be used as a relaxation technique to calm the mind and body, while also improving inner peace. When done before bedtime, it can reduce insomnia and other sleep problems by promoting overall calm. Meditation and sleep both contribute to the health of both body and mind in similar ways. Experienced meditators have been found to have less sleep and better mental acuity than non-meditators.
This has been demonstrated in many different studies, even for new meditators who begin with short periods of meditation. Rather than using meditation to replace sleep, use it to help you sleep better so you can receive the benefits mentioned above. Breathing exercises are a form of meditation that involve concentrating and regulating your breaths, eventually reducing them, which tells your mind that it's time to fall asleep. You can slowly increase the length of your meditation sessions and experiment with shorter sleep times.
However, keep in mind that meditation and sleep are two different things and neither can replace the other. If you're looking for better sleep, slow down and meditate.