At three months, babies sleep for different lengths of time at night. Some wake more often than others. To understand your baby’s sleep, look at naps as well as nights. One number cannot tell you whether your baby is sleeping well.
Sources: BIÖG
One night. Three different measures.
Three numbers with different meanings
Three terms help when comparing sleep. Night sleep is time actually asleep at night, leaving out known waking periods. The longest stretch is the longest sleep without waking. Total daily sleep includes naps too.
An invented example: from 8pm to 7am is eleven hours. If your baby was awake for one hour altogether, that is ten hours of night sleep. Add four hours of naps and the total is fourteen hours. These numbers explain the arithmetic; they are not a recommended schedule.
Why sleep charts give different numbers
An average shows how long a group of children slept. A recommendation gives a range suggested by experts. Both can help, but neither tells you exactly how much sleep your baby needs. Charts may also cover different ages.
The sleep experts at the AASM do not give a recommended sleep range for babies under four months. Babies vary widely, and there is not enough research to set a clear range. Do not use the figures for older babies as a target at three months.
Sources: Paruthi et al. (2016)
What to notice in everyday life
Use the same 24-hour window for comparisons, such as one morning to the next. Mark approximate times as approximate and leave missing entries as gaps. There is no need to watch your baby constantly to make the log exact.
Useful questions include: what has changed, how is feeding going, how does your baby seem while awake, and how are the adults coping? A short note may be more useful than a total number of hours.
Keep the sleep space safe
Place your baby on their back on a firm, flat mattress in a clear cot. Keep pillows, loose bedding and soft objects out. The German public-health source recommends a separate cot in the parents’ room during the first year. Safe-sleep principles apply to naps too.
Sources: BIÖG
When to seek support
Seek prompt medical advice for unusual sleepiness, difficulty waking, much poorer feeding or fewer wet diapers. For breathing difficulty or unresponsiveness, call your local emergency number. Ongoing parental exhaustion also deserves support.
Common questions
Must a three-month-old sleep through the night?
No. A fixed number of uninterrupted night hours is not a milestone every baby must achieve at this age.
Does drowsy feeding count as awake time?
The distinction can be unclear at home. Record what you observe and mark uncertain times. An everyday log is not a sleep study.
Sources & further information
The sources for this guide are linked below. Examples and everyday tips help explain the topic; they are not a personal plan for your baby. Sources last accessed on 20 September 2026.
- BIÖG: Das Wichtigste zum Schlaf im ersten Lebensjahr
German-language health resource; local guidance may differ.
- Paruthi et al. (2016): AASM-Konsens zur Schlafdauer
Professional guidance; see the linked publication for context.
- BIÖG: Sicher schlafen
German-language health resource; local guidance may differ.
- NHS: Dehydration
UK public-health guidance.
- DGSM: Schlafstörungen bei Säuglingen, Kleinkindern, Kindern und Jugendlichen
German-language health resource; local guidance may differ.
This guide was created with AI assistance and has not been medically reviewed. How we create our guides.
