FAQ | Singapore Drink Driving Limit, Penalties & BAC

The legal drink driving limit in Singapore is 80 milligrammes of alcohol per 100 millilitres of blood — the same threshold as 35 micrograms per 100ml of breath, which is roughly 0.08% BAC. This is set out in the Road Traffic Act and applies to all drivers.

There is no safe way to "drink up to the limit". The same drink affects two people differently depending on weight, gender, metabolism, food, and how recently they drank, so the only certain way to stay legal is not to drink before driving. You can also be charged with the separate offence of driving under the influence if drink has made you unfit to drive, even when your reading is below the limit. Our calculator estimates your blood alcohol content from what you have consumed — treat the result as guidance, and if you have any doubt, do not drive.

Drink driving penalties in Singapore are severe. Under section 67 of the Road Traffic Act, a first conviction for exceeding the prescribed limit (more than 35 µg of alcohol per 100 ml of breath or 80 mg per 100 ml of blood) — or for driving while unfit through drink — carries a fine of S$2,000–S$10,000 and/or up to 12 months' imprisonment, plus a mandatory disqualification of at least 2 years. The court sets the fine and disqualification along the AGC "Sentencing Tariffs for Drink Driving" according to the breath-alcohol reading.

A second or subsequent conviction raises the penalty to a fine of S$5,000–S$20,000 and up to 2 years' imprisonment, with a minimum 5-year disqualification (and potentially much longer or lifetime bans for repeat offenders). Since the 2019 Road Traffic (Amendment) Act, courts can also order forfeiture of the vehicle, and causing hurt or death while drink-driving is prosecuted as a grave offence with heavier mandatory jail terms. Note that drink-driving is dealt with through the courts (fines, jail and disqualification) and is not part of the DIPS demerit-points scheme.

Refusing to provide a breath specimen without a reasonable excuse is itself an offence in Singapore, and it is treated as seriously as drink driving. If the Traffic Police require you to take a breathalyser test at the roadside or a further evidential test, declining can lead to the same kind of penalties as being over the limit — a fine, disqualification, and possible imprisonment.

If a breath test indicates you are over the limit, you may be taken for a further breath or blood test that provides the evidential reading used in court. Trying to avoid testing does not help your position; it generally makes it worse. The sensible course is never to drive after drinking, so the question of a test never arises.

Yes. Singapore law has two separate offences. One is driving with a blood or breath alcohol level above the prescribed limit (80mg/100ml of blood, or 35µg/100ml of breath). The other is driving while under the influence of drink to the extent that you are incapable of having proper control of your vehicle — and this does not depend on a fixed number.

That means you can be charged even with a reading below 80mg/100ml if the police consider that drink has impaired your driving. Many people are noticeably affected — slower reactions, poorer judgement — well before they reach the legal limit. The safest approach is to treat zero as your limit whenever you intend to drive, rather than trying to gauge how close to 80mg/100ml you can get.

An online BAC calculator gives a useful estimate, not a guaranteed reading. It applies the Widmark formula — the method used in forensic toxicology — to your weight, sex, the amount and strength of what you drank, and the time elapsed. That produces a reasonable approximation of your blood alcohol content, but it cannot capture every individual factor.

Your real BAC also depends on your metabolism, how much food was in your stomach, your hydration, medication, and your general health, none of which a simple calculator fully measures. For that reason the result should be treated as guidance to help you plan — not as proof that you are under Singapore's 80mg/100ml limit. If the estimate is anywhere near the limit, do not drive.

A breathalyser reading shows how much alcohol is in your breath, which corresponds directly to your blood alcohol content. A genuinely sober person reads 0.00%. In Singapore you are over the drink driving limit at 35µg per 100ml of breath (80mg/100ml of blood, about 0.08% BAC). As a rough guide to what readings mean:

• 0.02%–0.05% BAC: mild relaxation and slightly reduced judgement — under the limit, but impairment has begun.
• 0.05%–0.08% BAC: noticeably slower reactions, weaker coordination, and reduced attention.
• 0.08% and above: over the legal limit in Singapore; clear impairment of motor skills and judgement.
• 0.20% and above: heavy impairment, possible memory loss, vomiting, and risk of losing consciousness.
• 0.30%–0.40% and above: risk of coma and death.

These bands are general estimates — the same reading affects people differently depending on weight, sex, and tolerance. Use our calculator to estimate your own BAC, and remember that any reading above zero narrows your safety margin behind the wheel.

There is no reliable number of drinks that keeps everyone under the 80mg/100ml limit. A standard drink in Singapore is roughly 10g of pure alcohol — about two-thirds of a regular can of beer, a small glass of wine, or a single measure of spirits — but how much that raises your BAC depends on your weight, sex, metabolism, and whether you have eaten.

Because of that variation, two people drinking the same amount can end up with very different readings, and the same person can be over the limit one night and under it another. There is also the separate driving under the influence offence, which can apply below the limit. The only dependable answer is that if you intend to drive, the safe amount is none — use our calculator to see how even a couple of drinks moves your estimated BAC.

In Singapore, your alcohol level — your blood alcohol content (BAC) — is measured in either blood or breath, and the drink driving limit is set for each. The prescribed limit is 80mg of alcohol per 100ml of blood or 35µg per 100ml of breath, which is about 0.08% BAC.

At the roadside, the Traffic Police use a breath test because it is quick and non-invasive; a further evidential breath or blood test may be taken afterwards. The blood and breath thresholds each have their own legal value and are not interchangeable by a simple conversion. Our calculator lets you switch between units so you can compare your estimate against whichever figure you have in mind.

Evidential breathalysers are accurate but not perfect, and they carry a small margin of error. Approved devices work within a tight tolerance, and that tolerance is built into how they are calibrated and approved for use as evidence. A reading close to the limit is therefore still treated as valid.

The margin does not give drivers a safety buffer. If a roadside or evidential test shows you are over the legal limit, you can be charged. Personal breathalysers sold to consumers are generally less accurate than police equipment and can drift over time, so they should be treated as a rough guide only. The safest course is never to drink and drive rather than to rely on a reading that sits close to the limit.

On average, your body clears roughly one standard drink per hour, but this is only a rule of thumb — body weight, sex, metabolism, food, and general health all change the pace. As a guide, it can take around 2 to 3 hours to clear a couple of drinks, and considerably longer after a bigger session.

This is why morning-after drink driving catches people out: if you drank heavily into the evening, you can still be over the limit the next morning, even after a full night's sleep. Sleep, coffee, food, and a shower may make you feel more awake, but they do not lower your BAC. The safest approach is to wait until you are certain all the alcohol has gone and you feel completely sober — and to use our calculator to estimate when that will be.

Personal breathalysers can give drivers an indication of their BAC before deciding whether to drive, particularly the morning after drinking. Consumer models vary widely in quality, and even good ones are less precise than the evidential equipment used by the Traffic Police.

Sensors in personal devices also lose accuracy as they age and need periodic recalibration, so a reading near the limit should never be taken as permission to drive. Treat a personal breathalyser as an awareness tool only: if it suggests you are anywhere close to the 80mg/100ml limit, do not get behind the wheel. The reliable readings — the ones used in court — come from approved police instruments.

Your body removes alcohol at a fairly steady rate — roughly 0.015% BAC per hour — and nothing reliably speeds this up. Starting from a BAC of 0.1% (100mg/100ml of blood), it would therefore take in the region of 6 to 8 hours for the alcohol to clear completely.

That figure is an estimate, not a guarantee. The actual time depends on your weight, sex, metabolism, whether you have eaten, and your general health, so two people who reach the same BAC can sober up at different speeds. It is also worth noting that 0.1% is above Singapore's 80mg/100ml (0.08%) limit, so you would be over the limit for some time before your BAC reaches zero. Use our calculator for a personalised estimate of your elimination time.

The honest answer is that you cannot sober up faster. Your liver breaks down alcohol at an essentially fixed rate, and only time lowers your blood alcohol content. Popular "remedies" — black coffee, a cold shower, fresh air, exercise, a big meal, or being sick — do not change how quickly alcohol leaves your system.

What some of these can do is make you feel more alert, and that is precisely the danger: feeling more awake while your BAC is still high can fool you into thinking you are fit to drive when you are not. Coffee, for example, masks tiredness without touching your alcohol level. Drinking water is sensible for rehydration but does not speed up sobering up. The only safe plan is to wait — use our calculator to estimate when your BAC should be back to zero.

In Singapore, a standard drink contains about 10g of pure alcohol. In practice that is roughly two-thirds of a regular 330ml can of beer at 5%, a small glass of wine, or a single measure of spirits. To estimate the pure alcohol in any drink, multiply its volume in millilitres by its strength (ABV %) and divide by 1,000, then by about 0.789 to convert from millilitres to grams.

The Health Promotion Board's low-risk guidance is to keep to no more than two standard drinks a day for men and one for women, with alcohol-free days. Counting standard drinks is also the easiest way to estimate how long alcohol will stay in your system, since the body clears roughly one standard drink per hour. None of this, however, makes any amount safe before driving.

How long alcohol stays in your system depends on what is being tested. Alcohol itself can usually be detected in your breath for up to about 24 hours, in blood for up to 24 hours, in urine for up to 48 hours (longer with specialised tests), in saliva for 1–5 days, and as traces in hair for up to 90 days.

These detection windows are much longer than the time it takes to become safe to drive. Your blood alcohol content falls steadily at roughly one standard drink per hour, so for everyday purposes the figure that matters is when your BAC drops below the legal limit and then to zero — typically a matter of hours after a moderate evening, not days. Detection times also vary with the amount you drank, your metabolism, and your overall health. Use our calculator for a personalised estimate of when your BAC should reach zero.

Under Singapore's Liquor Control (Supply and Consumption) Act, retail shops and supermarkets may only sell takeaway alcohol between 7am and 10:30pm. Drinking alcohol in public places is also banned from 10:30pm to 7am, and tighter rules apply in designated Liquor Control Zones such as Geylang and Little India, especially at weekends.

Licensed premises such as bars, restaurants, and clubs serve within the hours of their individual licences, which can extend later. The legal age to buy and drink alcohol in Singapore is 18. If you need exact rules for a specific area or event, check the current guidance, as restrictions can differ by zone and over festive periods.

Your liver does most of the work of breaking alcohol down, using enzymes to process it at a steady, limited rate. When you drink more than the liver can comfortably handle, the by-products of that process damage liver cells over time. This is why heavy or regular drinking is so closely linked to liver disease.

Alcohol-related liver damage usually develops in stages. The first is fatty liver disease, where fat builds up in the organ — often with no symptoms and partly reversible if you stop drinking. Continued heavy drinking can lead to alcoholic hepatitis (inflammation) and, eventually, cirrhosis, where healthy tissue is permanently replaced by scarring. Cirrhosis cannot be reversed. The clearest way to protect your liver is to keep within low-risk drinking guidance, have several alcohol-free days each week, and avoid heavy single sessions.

Drinking heavily over many years raises the risk of a wide range of serious health problems. Alcohol contributes to high blood pressure, heart disease, and stroke, and to lasting liver damage. It is also a recognised cause of several cancers — including cancers of the mouth, throat, oesophagus, breast, bowel, and liver — and there is no completely "safe" level that removes this risk entirely.

The effects are not only physical. Long-term drinking is linked to depression, anxiety, and memory and concentration problems, and can lead to alcohol dependence, which is hard to break without support. It can also strain relationships, work, and finances. Keeping within low-risk guidance — with alcohol-free days — is designed to keep these long-term risks low. Cutting down at any age reduces your risk.

Blood alcohol content (BAC) has a direct effect on behaviour and the way your mind works. At low levels (around 0.02%–0.05%), many people feel relaxed, more sociable, and more talkative, while their judgement is already slightly impaired. As BAC rises, those changes deepen — and they happen before you necessarily feel "drunk".

Above roughly 0.08% BAC, coordination, balance, and reaction time are clearly affected, self-control drops, and decision-making becomes poorer — which is why this is the drink driving limit in Singapore. Higher still, mood can swing quickly, inhibitions fall away, and the risk of accidents and of aggressive or regretted behaviour climbs sharply. Because alcohol weakens judgement, people routinely underestimate how impaired they are. Checking your estimated BAC with our calculator gives you an objective figure rather than relying on how in-control you feel.

Many people reach for a drink to unwind, and alcohol can feel as though it relieves stress in the moment because it is a sedative that briefly dampens tension. That short-term effect, however, is misleading and does not last.

Regular drinking tends to increase anxiety and stress over time. Alcohol disrupts sleep, lowers mood, and interferes with the brain chemistry that helps regulate emotion, so the day after drinking often brings more anxiety, not less. Using alcohol as a coping tool can also build a cycle of dependence, where more is needed for the same effect and stopping feels harder. Healthier ways to manage stress — exercise, good sleep, time outdoors, and talking to someone you trust — work without those costs. If stress or low mood is persistent, speaking to a doctor is a sensible step.

Sertraline is a widely used SSRI antidepressant. General medical guidance is that drinking alcohol while taking sertraline can make you feel drowsy, dizzy, or less alert, so it is often best to avoid alcohol for the first few days of treatment, until you can see how the medicine affects you.

There are good reasons for caution beyond drowsiness. Alcohol is itself a depressant, so it can worsen the low mood and anxiety the medication is prescribed to treat, and may blunt how well the treatment works. The combined sedative effect of alcohol and sertraline also makes activities such as driving especially risky, and how strongly the two interact varies from person to person. If you take sertraline, do not assume your alcohol tolerance is unchanged — and if you feel at all affected, do not drive. For advice tailored to your medicine and dose, speak to your doctor or pharmacist.

It can be hard to tell when drinking has tipped from a habit into a problem, partly because it often develops gradually. Common warning signs include a strong or constant urge to drink, struggling to control or stop once you start, needing more alcohol to get the same effect, and drinking to cope with stress, anxiety, or low mood.

Other signs are the knock-on effects: drinking that interferes with work, relationships, or responsibilities, neglecting other interests, feeling guilty about how much you drink, or experiencing withdrawal symptoms — such as sweating, shaking, or irritability — when you do not drink. Noticing one or two of these does not mean the worst, but it is a good reason to take stock. Help is available and effective: a doctor can offer advice and referral, and confidential support is available from community health services. Reaching out early makes change far easier.