Why are so many people against increasing the minimum wage?

Leaving aside the question of whether its actually true that "many" people are against it. Why would you be against a minimum wage increase? Well, the first thing to establish is that the economy is ultimately circular, and linked to that, businesses are just figments of our collective legal imagination used to organise people and stuff. This is important because it means phrases like "business will just do X" are actually meaningless. ""Businesses"" only exist on paper and cant actually "do" much. They are just really complicated structures for channeling value between the entities that actually matter - *people*. And when it comes to businesses there are (simplifying a little), three groups of people: customers (who put money in in exchange for whatever the business produces and sells), workers (people who put in time, expertise and labour to produce stuff in exchange for money), and owners (people who put in money to get the whole thing working in exhange for money out later). For a business to be viable all three groups need to find the value exchange offered by the enterprise to be worthwhile. If customers arent getting products and services they value more than the money they are paying, they stop buying. No money in means nothing to pay employees with and no returns for owners. If the employees are getting less money out then they value their time they wont work, and so nothing will get produced, so there are no products to sell (and by extension no returns for owners). Owners are a little different since what happens there is a the value of the ownership drops until it reflects a value exchange for the returns. The owners therefore run a risk of loss on their investment rather than them "withdrawing" from the process. Anything you do that influences businesses is really just influencing those three groups of people in some way. If you increase tax "on business" for example what you're really doing is extracting value from one, two or all three of those groups. Some of the value that would go to customers in terms of quality of the product being sold, or to employees as wages / benefits or to owners as returns, is instead taken by the government as tax. So, what is a minimum wage doing? Well its forcing the share of value the business is distributing to be artificially increased towards a subset of employees than otherwise. Is that a good thing? As with everything in economics.. it depends. First thing that should be apparent is that value needs to come from somewhere. Increasing the minimum wage doesnt create any new value, it just means shuffling round some of the existing value. And in turn that means there have to be losers. Customers lose if firms put prices up (either directly by charging more for the same product or by reducing the value of the product for the same price). In this case minimum wages transfer value from customers to low paid workers. Non-minimum wage workers lose by value that would have funded their pay rises or improved conditions being diverted to higher pay for min wage workers. In this case minimum wage is a transfer from non-min wage workers to min wage workers. Minimum wage workers themselves can "lose" (or at least end up non better off), when effectively future value that would have been used to fund their pay rises is brought forward. (This is the effect that you get a pay rise this year due to min wages going up, but then no pay rises for the next 5 years because you're already at the level pay would have got to anyway). In this case Min Wage is a transfer from future workers to current ones. Marginal workers are also effected, this occurs when a firm doesnt hire (or let's people go), to fund the cost of higher min wages. In this case minimum wage is effectively a value transfer from the marginally unemployed to min wage workers. And finally, owners lose when returns are reduced, so both their return and the value of this investment is reduced. This is a value transfer from owners to min wage workers. In practice it isnt just one of these. For many / all businesses it will be some combination of all of them. If you are against minimum wage rises its likely because you're judgement is that the costs to the various loser groups above outweighs the gains to the winner group.