The price the provider charges you is the amount he would like to get for his services.
Let's take an example, you do a blood test at a lab, and they charge you 1200.00$
If you have insurance, and the provider has a contract with that insurance (meaning 'they take them'), the contract limits what they can charge and what the will get.
For the example, that might be 21.56$. This is what the insurance pays them (or what you pay them, if you have deductible).
Note that if you have no insurance, you owe them 1200.00$. They are typically willing to negotiate that you only pay maybe 850.00$, but it still will be much higher than the insurance price. Why?
The reason is that the insurance-agreed payment of 21.56$ does not cover their cost (but the insurance forces them to make that contract or basically be out of business). Let's say for example they need 26.56$ to make a living on it; so they lose 5.00$ on every insured customer. One in 235 customers has no insurance, and his price is calculated as 26.56+235*5.00 = ~1200.00$, so his bill covers the losses for all insured 'under-payers' (all numbers are examples made up to illustrate the math the provider does).
My bloodwork typically comes between 800 and 1400, and gets reduced to around 20: so the numbers are not completely off. The ratio and concept works for doctors and hospitals the same, just not as significant a difference.