When should I tell my friends and family that I am having twins? After 12 weeks is a good time to tell them as the risk of vanishing twin syndrome and miscarriage decreases after 12 weeks. Also usually by 12 weeks you can tell if your pregnancy is going to be viable.
However if you’re suffering very badly from morning sickness, or extreme tiredness, you may have to tell them sooner.
When should I tell my boss that I am pregnant with twins? In the UK you must tell your boss you are pregnant ‘at least 15 weeks before the beginning of the week the baby is due.’ See https://www.gov.uk/working-when-pregnant-your-rights
If you’re working in an environment where you’re either expected to stand or sit for long periods of time, do heavy lifting, work with toxic chemicals, or if you have long working hours, you may be able to have your work duties adapted to suit your pregnant state. If your employer is not able to find you alternative lighter duties, you may be suspended on full pay.