There is little support for the view that school uniforms, on average, were cheaper than plain clothes.
Some plain clothes may cost more, while other plain clothes cost less than uniforms.
Whether school uniforms reduced peer pressure between students is actually another argument, discussed in more detail under bullying.
The point remains that any mandatory dress policy is restrictive, i.e. it rules out clothing that may well be cheaper.
It is this point that makes cost into an argument against school uniforms.
"because of school uniforms, parents do not have to buy many clothes for their children, which saves them time and money." [source]
"But most children will have plain clothes next to their school uniform. The idea of a school uniform is that students wear the uniform at school, but do not wear the uniform, say, at a disco or other events outside school. This effectively means that children will need a double set of clothing." [source]
"School uniforms are expensive, by their nature they are produced in limited numbers, they have to be special. Furthermore, school uniforms are typically made of polycotton, because if they were made of pure cotton, they would fade after a few washings and there would be color differences between the uniforms of various pupils, which goes against the very idea of uniformity. Therefore, school uniforms are far more expensive than the cheap cotton clothing people normally like to wear. The situation is also prone to exploitation by unfair trade practices, unhealthy schemes, favoratism and cronyism, e.g. deals in which secret bribes are paid for the privilege of exclusively and 'locally' producing and selling such school uniforms. One pays the price for not being able to choose the often cheap imports from countries such as China and India." [source]
"Why shouldn't it be up to families to decide how they spend their clothing budget? If you personally like to keep wearing the same thing, should you therefore impose your personal opinion upon others?" [source]
"School uniforms lower long term clothing costs (plaid jumpers or skirts wear forever and can be handed down)" [source]
"Not true, because other clothing are less expensive and can be handed down as well. I have a ton of clothing that was handed down to my son from older and larger friends that are like new - I cannot use them because they aren't within the uniform policy. Instead, I had to spend over $100 on uniforms at the beginning of the year and have had to replace uniform pants TWICE this year already because he's stained or torn out the knees. Unlike jeans, which I could cut off and hem to make into jean shorts, there are NO SHORTS allowed in the uniform policy, which means these pants with the knees torn out are now TRASH. $20 trash. Six pair of $20 trash so far this year. My kid isn't going to wear these clothes outside of school - he, like most other TA students hate these items. So, I am spending more and more money (which I don't have a lot of) on trash that he wears out. MAYBE he will be able to wear some of the shirts next year - or someone will, but the pants, which are the most expensive item, are junk." [source]
"Any clothes can be handed down. You can buy normal clothes that last long and pass them on to a brother or sister. Alternatively, you can buy cheap T-shirts and buy new ones later." [source]
"Furthermore, are uniforms really cheaper in the long term? You can buy clothes now for a cheap price that would have cost you much more a few years back. Uniforms are typically more expensive to start with, especially compared to the cheap T-shirts, jeans and other clothes one can buy off the shelf. Most students will also have another set of clothing, next to their uniform, e.g. when they go shopping or sightseeing. So, there will also be the cost of normal clothes, on top of that the cost of a uniform." [source]
"Even for the school there will be the extra cost, in the form of time and money that has to be spent on checking uniforms, on suspensions for breaches, of courtcases, appeals, challenges, precautions to avoid favoratism in selection of manufacturers, etc." [source]
"School uniforms reduce pressure on students to wear expensive clothes, or to avoid wearing the same clothes the next day." - anonymous
"Few people will notice that a student comes to school wearing the same jeans and T-shirt the next day. Anyway, jeans and T-shirts can be bought so cheap off the shelves that one can easily buy a few of them in different colors and styles, for the same price as a uniform." - anonymous