The firm will launch the scheme in September for people who have just completed their A-Levels or equivalent.
It is the latest scheme from the firm, which already has a well-established graduate programme and a school-leaver scheme.
Applicants will go through a recruitment process and roughly five successful candidates will begin a three year course.
This will cover basic bookkeeping skills and go onto financial planning qualification.
Ken Hughes, group HR manager, said: “University is not for everyone and neither is going straight into a job. Our programme offers an alternative, a kind of half-way house between further education and work.
“Trainees are given the chance to establish themselves in the work place and start earning a living but also continue learning and gaining new skills and qualifications along the way.”
The firm is based in the West Country with offices in Exeter, Melksham, Dorchester, Yeovil and Shepton Mallet.
It is hoping to find applicants in the local area and encourage other local firms to adopt similar schemes.
Mr Hughes said: “Old Mill has always had a strong sense of community- we are all local people with a genuine passion for the area in which we work and live- and we wanted to be able to offer something back to the community.”
For more information about the scheme contact Ken Hughes on 01935 709355 or email This email address is being protected from spambots. You need JavaScript enabled to view it.