You should sponsor your employee for as long as you expect to require them to hold the role they are being sponsored to do. The maximum initial duration of sponsorship is 5 years but there is no restriction on the amount of times that this can be extended, provided they still meet the eligibility requirements.
The upfront fees payable increase if sponsorship is for more than 3 years so most employers sponsor their employee for 3 years and then they subsequently extend the visa for a further period of 3 years or less.
The length of the sponsorship period may also impact on the minimum salary that you have to pay the individual. Please contact us to discuss this further.
After 5 years, the employee can apply for Indefinite Leave Remain.