Combination Feeding: Breast and Bottle Together

Combination feeding — using both the breast and the bottle — is one of the most common patterns in infant feeding. In most countries, the majority of babies who start at the breast end up combination fed at some point before weaning. Families reach this pattern for all kinds of reasons: work, sleep, shared caregiving, milk supply, medical advice, or simply what feels right and sustainable.

There is no single correct ratio. The most useful framing is practical: what rhythm lets you feed your baby reliably and keeps the household sane? Both the NHS and WHO are clear that any amount of breast milk has value, and that combination feeding is a fully supported choice.

What Combination Feeding Can Look Like

The term covers a wide range of patterns:

• One bottle at bedtime, breastfeeding during the day
• Daycare bottles, nursing before and after work
• Top-ups after nursing, for babies whose intake needs a boost
• Night bottles given by a partner, nursing during the day
• Mostly breastfeeding with occasional formula bottles, so any caregiver can step in
• Mostly formula with a morning or bedtime nursing session, for comfort and connection
• Expressed milk bottles for times when direct nursing is not possible

Any of these is a legitimate way to feed a baby.

When to Introduce the First Bottle

If you plan to combine breastfeeding with bottles, timing the introduction matters.

Most lactation specialists suggest waiting until breastfeeding is well established — around 3–6 weeks — before offering the first bottle. Introducing bottles too early, while a nursing rhythm is still being built, can interfere with supply and latch. Waiting too long (beyond 8–10 weeks without any bottle) often means the baby has developed a strong preference for the breast and acceptance becomes harder.

A few things that help with the introduction:

• Let someone other than the nursing parent offer the first bottle, if possible — the baby is less likely to protest when they cannot smell milk nearby
• Try at a calm moment when the baby is alert but not frantically hungry
• Use a slow-flow nipple and let the baby draw the teat in themselves, rather than pushing it in
• Keep warm physical contact throughout — a bottle is not a reason to hold the baby any differently

Once a bottle is accepted, offering one every 2–3 days keeps the skill fresh without disrupting nursing. For more detail on technique and handling refusal, see our guide on introducing a bottle to a breastfed baby.

When Supplementation Is Medically Recommended

Sometimes combination feeding starts not as a preference but as medical guidance. A midwife, health visitor, or paediatrician may recommend formula top-ups if:

• Your baby has lost more than 10% of birth weight and is not regaining it at the expected pace
• Your baby has jaundice that needs additional fluid or calories to resolve
• Your baby is not producing the expected number of wet or dirty nappies
• There are concerns about milk transfer — the baby is nursing but not receiving enough milk

If you're in this situation, the guidance is: follow the advice you've been given, and protect your supply at the same time. Pumping or hand-expressing at each feed where a top-up is given helps signal the body to continue producing. As feeding improves and weight gain stabilises, a lactation consultant can help you work toward reducing top-ups if that's your goal.

Medical supplementation isn't a failure. It's a short-term, evidence-based intervention. Many parents who start with medically indicated top-ups go on to breastfeed for months.

Protecting Milk Supply

Supply responds to demand. The key principle:

> If a nursing session is replaced by a bottle, the breast still needs the demand signal.

In practice that usually means:

• Pumping at the same time the baby would have nursed, even a short session
• Storing the expressed milk for future bottles
• Continuing to nurse outside the bottle-replaced feeds

If bottles are added without any pumping to replace the skipped feeds, supply will typically adjust downward over 1–2 weeks at that time of day. That's fine if it's intentional. It's frustrating if it isn't what you planned — and is the most common reason supply drops unexpectedly after introducing bottles.

Avoiding Bottle Preference

Babies can start to prefer the bottle if it feels noticeably easier than the breast. The two main levers:

• Flow. Slow-flow nipples at every age — faster flow makes the bottle effort-free by comparison.
• Pace. Paced, responsive bottle feeding keeps the effort closer to nursing.

See our paced bottle feeding guide for a full walk-through.

Additional habits that help:

• Holding the baby close in a nursing-like position
• Switching sides halfway through the bottle
• Skin-to-skin time around feeds
• Keeping eye contact during the bottle, as you would at the breast

If a baby has already started preferring the bottle, frequent nursing with plenty of skin-to-skin and shorter, more frequent sessions — rather than longer, less frequent ones — often helps reset the balance. A lactation consultant can identify specific adjustments.

Mixing Formula and Expressed Breast Milk

You can combine formula and expressed breast milk in the same bottle — a practical option for top-up feeds or when supply is lower at a particular time of day.

How to mix safely: Prepare the formula first using freshly boiled water cooled to around 70 °C (158 °F), following the tin's instructions exactly. Once the formula has reached a safe drinking temperature, add the expressed breast milk. Never use breast milk in place of water when preparing formula powder — this would over-concentrate the feed and strain the baby's kidneys.

Store mixed bottles in the back of the fridge and use within 24 hours. Keep portions small (60–90 ml / 2–3 oz for top-ups) to reduce waste, since any milk left in a bottle after a feed should be discarded within 1–2 hours.

If you're introducing formula for the first time, start with a small amount alongside expressed milk. The taste differs from breast milk, and a gradual introduction often makes acceptance smoother.

Moving from Full Nursing to Combination Feeding

If you're transitioning on a timeline — returning to work, a planned trip, or any other reason — a gradual swap is almost always easier than a sudden change.

A typical gentle schedule:

1. Choose the first feed to replace. Mid-afternoon is often the easiest — supply is typically a bit lower and feeds are often shorter.
2. Offer a bottle instead. Pump at that time if you want to maintain supply.
3. Wait 3–5 days before replacing another feed. This gives your breasts and the baby time to adjust.
4. Continue swapping one feed at a time until you reach the rhythm you want.
5. Keep bedtime and first-morning feeds until last if you want to hold on to the most established comfort sessions.

Breastfeeding tends to stay reliable in the morning and at bedtime even as daytime feeds move to bottles, because those sessions are typically the best-established and the most hormonally supported.

Choosing What Goes in the Bottle

• Expressed breast milk — nutritionally identical to nursing, ideal when supply allows.
• Formula — provides full nutrition. Follow the preparation guidance exactly (see our formula preparation guide).
• A mix of expressed milk and formula — fine to combine safely (see above).

There is no hierarchy here. Many families use expressed milk in daycare bottles and formula at bedtime, or vice versa, depending on supply and convenience.

Consistency Across Caregivers

When multiple people share the feeding — a partner, a grandparent, a childminder — consistent technique matters more than it might seem. Ask all caregivers to:

• Use the same slow-flow nipple
• Follow the paced feeding approach
• Stop at fullness cues, not at a fixed volume
• Burp at natural pauses, not only at the end

A brief conversation and a note on the fridge go a long way. Inconsistent technique is one of the more common reasons bottle preference or overfeeding develops gradually across different caregivers.

Going Back to Full Breastfeeding

Re-lactation — rebuilding a milk supply that has reduced — is possible, and many families do it successfully. The approach typically involves:

• Nursing as frequently as possible, including at night, to drive prolactin
• Skin-to-skin contact during and between feeds, which supports letdown
• Pumping between nursing sessions to add stimulation
• Gradually reducing bottles, replacing them with nursing sessions as supply builds

Many parents see meaningful progress within 1–3 weeks. The earlier re-lactation begins after a reduction in nursing, the more responsive the body tends to be. An IBCLC can guide the process and set realistic expectations specific to your situation.

When Combination Feeding Is a Relief

It's worth naming this part. A lot of families discover that shared bottle feeding is the piece that makes feeding sustainable — a partner who can take a night feed, a caregiver who can step in on a difficult day, a reliable way to feed the baby when supply wobbles.

These are real benefits, not compromises. Feeling guilty about introducing bottles is extremely common, and extremely unnecessary. What matters is that the baby is growing, and that the adults in the house aren't running on empty.

When to Ask for Help

Talk to a midwife, health visitor, IBCLC, or paediatrician if:

• Supply drops more than you intended and you want to rebuild it
• The baby starts refusing the breast after bottles are introduced
• You're unsure whether the baby is getting enough milk overall
• The transition is causing physical discomfort (engorgement, blocked ducts)
• Formula top-ups are needed after most feeds and you're not sure why
• You want to reduce or stop top-ups and need support with the transition

These are all common situations with good practical fixes. Early support almost always shortens the uncertainty.

Log Both Sides of the Rhythm

Combination feeding adds up to a lot of moving parts — nursing sessions, pumping sessions, bottles of expressed milk, bottles of formula, who fed last, how much. Flaske gives you a single calm view of the bottle side, and pairs well with Amme for the nursing side.

With Flaske, you can:

• Log bottles of expressed milk and formula in a few taps
• See daily intake across caregivers without mental maths
• Share a synced view with your partner through private iCloud sync
• Spot the rhythm across the week

Flaske uses private iCloud sync so your feeding records stay inside your own iCloud account, visible only to the caregivers you invite.

Learn more about Flaske

Related Reading

• Introducing a Bottle — step-by-step guidance on the first bottle for a breastfed baby, including who should offer it and how to handle refusal
• Paced Bottle Feeding — how to pace a bottle feed so the baby stays comfortable and flexible between breast and bottle
• Preparing Formula Safely — water temperature, mixing steps, and safe storage times
• Low Milk Supply — what genuinely affects supply and the steps most likely to help
• Pumping at Work — how to maintain supply while managing bottles away from home

References

This article draws on guidance from NHS: Combining breast and bottle.

Additional references:

1. World Health Organization. Breastfeeding. WHO; 2023.
2. La Leche League International. Bottle feeding a breastfed baby. LLLI; 2023.
3. Academy of Breastfeeding Medicine. ABM Protocol #3: Supplementary Feedings in the Healthy Term Breastfed Neonate. Breastfeeding Medicine. 2017. DOI: 10.1089/bfm.2017.0014.
4. CDC. Breastfeeding FAQs — Some Common Concerns. US Centers for Disease Control and Prevention; 2023.
5. Ammehjelpen. Delvis amming. Accessed 2026-04-22.

This content is for informational purposes only and does not replace professional medical advice. Consult your healthcare provider for personalised guidance.