Cold or Flu? How to Tell the Difference and How Long Each Lasts (UK)

Cold vs flu vs COVID-19: symptoms table

All three circulate together in autumn and winter. Here’s how they usually compare, based on the NHS symptom pages.

Flu also often brings a headache, and COVID-19 can cause shortness of breath, diarrhoea or feeling sick. Symptoms overlap, so it isn’t always possible to tell them apart.

How to tell if it’s a cold or flu

Ask yourself three questions:

1. How fast did it come on? A cold builds over a couple of days. Flu can go from fine to floored in a few hours.
2. Where is it? A cold stays mainly in your nose and throat. Flu hits your whole body with fever and aches.
3. Could you go to work? With a cold, most people can carry on. With flu, you’re usually too exhausted.

Either way, if you have a high temperature or don’t feel well enough for normal activities, the NHS says stay at home and avoid other people until you feel better.

Could it be COVID-19?

COVID-19 symptoms overlap with both a cold and flu, so you can’t always tell from symptoms alone. The NHS lists a high temperature or shivering, a new continuous cough, a loss or change to your sense of smell or taste, shortness of breath, tiredness, an aching body, a headache, a sore throat, a blocked or runny nose, loss of appetite, diarrhoea, and feeling or being sick.

The advice is the same as for a cold or flu: try to stay at home and avoid other people while you have a high temperature or don’t feel well enough for normal activities. If you test positive, the NHS says adults should stay at home for 5 days after the day of the test (3 days for under 18s) and avoid people at higher risk of serious illness for 10 days.

How long do a cold and flu last, and how long are you contagious?

A cold usually lasts about 7 to 10 days in adults, and the NHS says you should begin to feel better within 1 to 2 weeks. Flu is shorter but harder: most people feel better within a week, though a cough and tiredness can hang on for a few more weeks. You’re contagious with a cold until all your symptoms have gone, and with flu you’re most likely to pass it on in the first 5 days.

How long does a cold last?

Cold symptoms usually appear within a day or two of catching the virus and build over 2 to 3 days. NI Direct puts a typical cold at about 7 to 10 days in adults and older children, and around 10 to 14 days in children under 5. A cough can outlast the other symptoms. See a GP if your symptoms haven’t improved after 10 days or a cough lasts more than 3 weeks.

How long does the flu last?

Flu symptoms usually start 1 to 3 days after you’re infected and come on within hours. According to NHS inform, most people feel better within a week, but you may have a lingering cough and still feel very tired for a few more weeks. The NHS says to get an urgent GP appointment or call 111 if your symptoms haven’t improved after 7 days.

How long are you contagious?

With a cold, you can start spreading it a few days before symptoms begin, and you stay infectious until all your symptoms have gone. With flu, you’re most likely to pass it on in the first 5 days after getting infected. Young children can stay infectious for longer with both.

Cold and flu germs can live on hands and surfaces for 24 hours, so wash your hands often, catch coughs and sneezes in a tissue and bin it straight away.

iStill exhausted weeks later? If it doesn’t lift, see why you might always feel tired and feeling tired in winter, and speak to your GP.

Is it a chest infection?

A chest infection often follows a cold or flu. The difference is that it settles in your chest rather than your nose and throat. The NHS lists these symptoms:

• a chesty cough, which may bring up green or yellow mucus
• wheezing and shortness of breath
• chest pain or discomfort
• a high temperature, headache, aching muscles and tiredness

Most chest infections are viral and clear up on their own. Symptoms usually ease within 7 to 10 days, but the cough and mucus can last up to 3 weeks. Rest, drink plenty of fluids and prop your head up in bed to make breathing easier at night (more in our guide to coughing at night). Antibiotics are only used for bacterial chest infections, such as some types of pneumonia.

iSee a GP if you feel very unwell or worse, you cough up blood or blood-stained mucus, a cough lasts more than 3 weeks, or you’re pregnant, over 65, have a weakened immune system or a long-term heart, lung or kidney condition. Read the full NHS chest infection page for details.

How to recover faster from a cold or flu

Honestly? There’s no way to get rid of a cold in 24 hours or overnight. Colds and flu are viruses that run their course. What you can do is ease the symptoms and give your body the best chance to recover. The NHS advice:

• Rest and sleep. If a blocked nose keeps you awake, see how to sleep with a cold for positions and bedtime tips.
• Drink plenty of fluids. For flu, the NHS says your pee should be light yellow or clear. See how much water you should drink.
• Eat healthy food when you can.
• Try a warm lemon and honey drink, or a soothing caffeine-free tea such as chamomile.
• Gargle with salt water for a sore throat (adults only).
• Breathe in steam for a blocked nose, for example in a hot shower.
• Take paracetamol or ibuprofen for aches and a high temperature, following the leaflet.
• Don’t smoke, as it can make symptoms worse.

For flu, the NHS advice is the same core trio: rest and sleep, paracetamol or ibuprofen to bring down a temperature and ease aches, and plenty of water. Never give aspirin to anyone under 16.

iA pharmacist can suggest decongestants and cold and flu remedies that suit you and check them against medicines you already take. Many of these remedies already contain paracetamol, so don’t take extra paracetamol alongside them.

What doesn’t work: antibiotics. GPs don’t recommend them for colds or flu because antibiotics don’t work on viruses.

How to get over a cold faster

There’s no cure, and the NHS says you should begin to feel better in about 1 to 2 weeks. The quickest realistic route is to stop the symptoms wearing you down:

1. First few days: rest, keep your fluids up and take paracetamol or ibuprofen if they’re suitable for you. Gargle salt water for a sore throat (adults only): see sore throat remedies.
2. At night: protect your sleep, because a blocked nose can wreck it. See how to sleep with a cold.
3. Blocked nose: ask a pharmacist about a decongestant. The NHS says not to use nasal sprays for more than a week.
4. Zinc: a 2024 Cochrane review found zinc taken once a cold starts may slightly shorten it, by around 2 days, but the evidence is low certainty. See the evidence table.

iAntibiotics won’t speed it up. See a GP if you’re not improving after 10 days.

Vitamin C, zinc, honey and echinacea: the evidence

Here’s what the best reviews found for the most popular remedies. No supplement or remedy cures a cold.

The NHS says there’s little evidence that vitamin C, echinacea or garlic prevent colds or speed up recovery. For the bigger picture, see how to support your immune system and what doesn’t work, and for how the two minerals differ, magnesium vs zinc.

Cold and flu medicines: using them safely

Cold and flu products often share the same few ingredients. A few rules keep you safe:

• Don’t double up on paracetamol. Many cold and flu remedies already contain it, so taking extra makes it easy to go over the safe dose.
• Use one decongestant at a time. Don’t combine two nasal sprays, or a spray with tablets.
• Nasal sprays and drops: no more than 5 days at a time.
• High blood pressure: check with a pharmacist or GP before taking a decongestant, as you should with diabetes, heart, thyroid, liver or kidney problems, glaucoma or other medicines.
• Pregnant: only use decongestants if a healthcare professional advises it, and ask a pharmacist before any cold medicine.
• Breastfeeding: decongestant tablets, liquids and powders aren’t recommended. Some nasal sprays may be fine, but ask a pharmacist first.

Cold and flu tablets when pregnant or breastfeeding

Paracetamol is usually the first choice for a cold or flu if you’re pregnant or breastfeeding, along with rest and fluids. Many combination cold and flu tablets also contain a decongestant such as pseudoephedrine or phenylephrine, which isn’t recommended in pregnancy and may reduce your milk supply. Always ask a pharmacist and read the leaflet first.

• Pregnant: the UK Medicines in Pregnancy service (bumps) says to avoid ibuprofen and decongestant tablets, sprays and drops. Some versions of well-known cold and flu brands contain a decongestant, so check every product, not just the brand name.
• Breastfeeding: the NHS says decongestants you swallow aren’t recommended, and that pseudoephedrine may reduce the amount of milk you make. Paracetamol is fine, but check with a GP, midwife or pharmacist if it’s combined with other medicines.
• Flu vaccine: it’s free on the NHS at any stage of pregnancy (see who can get it).

Colds and flu in children

Young children can stay infectious with a cold for longer than adults, and may be irritable, struggle to feed and sleep, or vomit after coughing. Children with flu can also have ear pain and swollen glands, and seem less active.

Safety first:

• Paracetamol or ibuprofen can help a distressed child with a high temperature. Check the leaflet for the right medicine and dose for their age, or ask a pharmacist.
• Never give aspirin to anyone under 16.
• Don’t give decongestants to children under 6. For 6 to 11 year olds, ask a pharmacist first.
• Don’t give honey to babies under 12 months, or hot drinks to small children.
• No steam bowls for children: they can scald.
• Keep them drinking and watch for dehydration, such as fewer wet nappies.

Call 111 if a baby under 3 months has a temperature of 38C or more, a baby aged 3 to 6 months has 39C or more, a fever has lasted 5 days, or you’re worried. Call 999 for a rash that doesn’t fade under a glass, a stiff neck, difficulty breathing, blue or grey lips, or a child who is hard to wake.

All Evopure products are for adults (18+) only.

When to see a GP, and red flags for 111 or 999

Most colds and flu get better on their own. Get help if:

See a GP if you have a cold and:

• you have a high temperature for more than 3 days, or feel hot and shivery, or symptoms get worse
• you feel short of breath or have chest pain
• your symptoms haven’t improved after 10 days, or a cough has lasted more than 3 weeks
• you have a long-term medical condition or a weakened immune system

Get an urgent GP appointment or call 111 if you have flu symptoms and:

• you’re 65 or over, pregnant or have recently given birth
• you have a long-term condition or a weakened immune system
• you feel very unwell or short of breath
• your symptoms haven’t improved after 7 days

A doctor may offer antiviral medicine to some people at higher risk.

Red flags: call 999 or go to A&E if you have:

• sudden chest pain
• severe difficulty breathing, such as gasping, choking or not being able to finish sentences
• pale, blue or blotchy skin, lips or tongue
• coughing up blood
• sudden confusion, for example not knowing where you are
• collapsed or fainted
• a rash that does not fade when you press a glass against it
• a stiff neck and you can’t look at bright lights, or a very painful headache
• a seizure (fit) for the first time

The last three can be signs of meningitis. For the glass test, press the side of a clear glass firmly against the skin: if the spots don’t fade, call 999. Not everyone with meningitis gets a rash, and the rash can be harder to see on brown or black skin, so don’t wait for one if someone seems seriously ill. Don’t drive yourself to A&E: ask someone to take you or call 999. More on the NHS meningitis page.

Not sure how urgent it is? Call 111 or use NHS 111 online, any time of day.

The flu vaccine this autumn: who can get it free

The NHS advises getting the flu jab as soon as you can (it doesn’t protect against colds). For winter 2026 to 2027 it’s free for adults who are:

• aged 65 or over, including those who’ll be 65 by 31 March 2027
• aged 18 to 64 with certain long-term health conditions
• pregnant, or living in a care home
• the main carer for an older or disabled person, or receive Carer’s Allowance
• living with someone who has a weakened immune system
• aged 16 or over and sleeping rough or in a hostel or night shelter
• frontline health and social care workers (through their employer)

Children aged 2 or 3 on 31 August 2026, school children from reception to year 11, and children from 6 months with certain long-term conditions are offered it too, usually as a nasal spray. Adults can book online, in the NHS App, at a pharmacy or through their GP, up to 31 March 2027.

More ideas for staying well in our winter wellness guide.

Vitamin D in winter

Between October and early March, UK sunlight isn’t strong enough to make the vitamin D you need, so the NHS says everyone, including pregnant and breastfeeding women, should consider a daily supplement of 10 micrograms of vitamin D in autumn and winter. Don’t take more than 100 micrograms a day. Read more in how much vitamin D to take in winter and vitamin D deficiency symptoms.

Vitamin D isn’t a cold or flu remedy, and no supplement cures a cold. Take it because the NHS advises it for everyone in winter.

If you already use CBD oil, our Evolabs Mint CBD Oil with vitamin D3 combines high-quality, tested CBD with 10 micrograms (200% NRV) of vegan, algae-based vitamin D3 per half pipette, the NHS daily amount. Vitamin D contributes to the normal function of the immune system. The CBD itself has no authorised health claims, and we make no claim that this oil prevents or treats colds or flu. Read why we added algae-based D3 and our CBD dosage guide.

None of our products treats or prevents a cold or flu. If you’re putting together a calm evening routine while you recover, our Magnesium Glycinate Sleep Complex provides 290mg of magnesium per serving, and magnesium contributes to a reduction of tiredness and fatigue. Our Reishi Mushroom Adaptogenic Complex is a reishi hot chocolate made with cacao, so it contains a little natural caffeine.

It’s for adults (18+) only. We don’t recommend our products during pregnancy or breastfeeding; take a plain vitamin D supplement instead.

The FSA’s 10mg a day figure is precautionary advice rather than a legal limit, set while longer-term safety research continues. At Evopure we think it is a very cautious figure, and many adults use more. If you go above it, increase slowly, and check with your GP or pharmacist first if you take any medication.

Related guides

• A runny or blocked nose that lasts for weeks with no fever is more likely to be an allergy; see our guide to dust mite allergy symptoms.
• Sore throat remedies that actually help.
• Cough at night: causes and what helps.
• Pressure behind your eyes after a cold can be sinusitis; see headache behind the eyes.
• If you’re aching all over without other cold or flu symptoms, see our guide to body aches: causes and when to worry.
• Colds and fevers are a common trigger for cold sores; our guide covers the stages and how to avoid spreading one.
• Thinking of trying elderberry syrup? Read does elderberry work for colds and flu? first.
• For the full evidence on one of the most popular herbal cold remedies, see does echinacea work for colds?
• Manuka honey: what the evidence really shows.
• Does garlic help colds?
• If you’ve just had yours, see flu jab side effects: what’s normal and how long it lasts.
• Prescribed antibiotics for a chest infection and taking CBD? See CBD and antibiotics: which interact.
• The difference between vitamin D and D3.
• For what the Cochrane review found on lozenges, see zinc for colds: does it work?
• Thinking of a ginger shot for a cold? Here is what ginger shots can and can’t do.