There are many ways an attorney might charge a client for legal representation and work. These include retainer, flat fee, or contingency fee.
A retainer fee is a sum of money paid by the client to the attorney up front before the attorney will begin working on the client’s case. This money is placed in an account that is separate from the attorney’s operating account, and then the attorney will bill their time against it as the case progresses. This should all be explained in a written retainer agreement, which your attorney should explain to you before you sign. This should state how you will be charged and what will happen if your retainer fee is reduced to zero before the case is completed.
A flat fee is a single amount of money paid by the client in return for a single legal service performed by the attorney. This is usually used for legal work that will not require ongoing representation, i.e. a one-time event such as will-drafting or handling a real estate transaction.
A contingency fee is a percentage of the “winnings” either awarded to the client by the court after a trial has occurred, or paid to the client from the defendant via settlement agreement. The attorney will not get paid unless the client wins the case. Typically, contingency fees are charged for a personal injury case, where a client is suing someone for a wrong against a client. Contingency fees are not allowed in certain kinds of proceedings, such as criminal defense or divorce representation. Attorney fees cannot be contingent upon any specific outcome in those types of proceedings.