Hertsmere has one of the highest booster jab take-ups among over 50s in the whole of England, figures show.
Just over 29,000 people living in the borough over the age of 60 have received a third Covid vaccine, NHS England data up to November 28 shows.
Based on population estimates by the Office for National Statistics, this suggests around 73.5 per cent of Hertsmere's over 50s have received the maximum possible protection against Covid-19.
According to a list of all local authorities in England by the PA news agency, Hertsmere's proportion of 73.5 per cent is the fourth highest.
Only Stratford-upon-Avon (76.3 per cent), Hart, in Hampshire (75.4 per cent) and Warwick (74.1) per cent have recorded a higher proportion.
Hertsmere's position has been elevated by a higher uptake in locations such as Bushey Heath, where there is a larger elderly population.
The proportion of over 50s in Watford who have had three jabs is 63.5 per cent with around 18,500 people taking up the booster.
In Three Rivers district, just over 24,000 have been triple-jabbed, representing around 67.7 per cent of the over 50s population.
The lowest take-up in England is in the London borough of Tower Hamlets, where only 34.6 per cent of over 50s are estimated to have had a booster.
Following the emergence of the Omicron Covid variant, which has been identified in Three Rivers, the Government has accelerated the booster Covid vaccine programme.
The Government has said all eligible adults in England aged 18 and over will be offered a booster dose by the end of January.
The time between a second dose and a booster is being reduced from six months to three.
Dr Jenny Harries, Chief Executive of UK Health Security Agency, said: "Vaccination is critical to help us bolster our defences against this new variant – please get your first, second, third or booster jab without delay.
"A booster dose for everyone over 18 years is now recommended and will be available at a minimum of 3 months from your last primary course jab. Please take up this offer as soon as you are eligible to protect yourself, your families and your communities.
"Please make sure to wear a mask in line with government guidance, including on public transport and in shops, to help break the chains of transmission and slow the spread of this new variant."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here