The average salary for a registered dietitian in the US is around $38,974 to $70,643 per year. PayScale reported their median salary to be $50,154. Dietitians are actually paid a basic salary of $38,239 to $63,304, a bonus of up to $1,497, and profit sharing of up to $983.The starting salary for dietitians is around $38,291 to $51,299 per year. As they grow in this occupation, they receive more.egistered dietitian salary in the UK. The average salary for starting registered dietitians in the UK, based on Prospects, is Â£21,176 to Â£27,625 per year. Dietitians who are at a specialist level earn Â£25,528 to Â£34,189, while those who are at an advanced level make around Â£30,460 to Â£34,189.