That's the common way, but economically the difference should be significantly bigger, both when working more and when working less.

Any job comes with tasks that take a mostly unchangeable amount of time, team meetings for instance. As a result, the productive time (where people can actually produce) is reduced/increased by more than the contractual hours change. Likewise with certain costs a job causes, your desk for instance costs the same whether you work four or five days, this reduces the employee's profitability further when the hours worked are reduced.

TTYL's friend makes a good enough job to warrant suggesting an increase in the hours worked. Not only should that result in at least 25% increase, it's also good argumentative ammo to bargain for an actual pay increase. A paycut per hour worked seems to run completely against all logic.

You can argue it either way. There are certain fixed costs involved with having a job and if these fixed costs are already covered by 4 days work you don't need as much income for the 5th day. In the end it's supply and demand and an opportunity to negotiate, for both sides.

accept the job working 4.7 days a week

I went from a 50% job to 100% (same employer obv.). A drop of (made up figures) 1000 a day to 850 a day. (My example earns more than yours!)

The reason was the absolute cost of employment. Essentially, I was being paid at a premium rate when I was on 50%. There's no way they could pay 1000 a day 260 days a year. It was all very amicable and negotiated. I'm happy with what we agreed on.

So really it depends on the actual salary, the work involved and whether the parttime rate is in fact rather generous.

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Down with racism. Long live miscegenation!

Usually companies make offers based on a 100% salary and reduce accordingly if you work 80%.

Some allowances however are at times a fixed amount, example a company which would subsides health insurance or give a car allowance.

So it's usually base pay only that follows the % rules and other things may or not.

If in your case you are talking total pay, have a look at the details. If its base pay only, then indeed from 80 to 100% (i.e. 4 to 5 days a week) the increase should be 25%.

I think my friend deserves the same rate as he is getting now. We are not talking sums that the boss can't give or my friend does not rightly deserve. Yes all calculations get based on 100% wage.

My friend has been loyal to the company through ups and downs for years. He is not on premium wages. They actually would even take him back 100%, but my friend had reduced in the past for work-life balance reasons.

There is other sly stuff that the boss has slipped into the contract which is not right from employee rights point of view. I have advised my friend to look for a new job no matter what the outcome.

Being 'loyal' is the problem here, unfortunately it seldom pays off.

I bring news!

My friend called me at lunchtime and said that the boss tried the "bulk purchase" line. My friend did not budge and got the correct per hour rate!

I told the IT director at once place I worked, that I am as loyal to the company exactly as much as the company is loyal to me. He was shocked - he felt employees should be grateful that they've been given a job. I was a bit surprised and he was quite a good person to work for.