In the US, like marriage laws, divorce is also the province of the state governments. The federal government has got nothing to do with divorce laws. This is why the length of time you need to obtain a divorce varies based on state laws and the individual facts related to your case.

Also it is a legal process there are various issues related to spousal support, child custody, child support, distribution of property and division of debt and so on that need to be handled by the court for the dissolution of the marriage. For all these factors, you need to have time. There is nothing like you file for a divorce petition in a local court and you get the order after one week. For a termination of marriage to take place, you must be ready to devote some time.

There are several factors the play a key role in deciding the time required to get the final order. Some of the factors include:

• Whether the cases is contested or uncontested
• The amount of assets that need to be divides between the couple
• Child custody issues
• Whether your state requires a legal separation or waiting period before divorce
• Whether you had a covenant marriage
• If there is a prenuptial agreement in place
• The amount of time it takes courts in your jurisdiction to issue a final decree

If you want a fast process or an annulment, you should first consult with an experienced and well known attorney to determine what your rights are, what the applicable laws are, and how long the process will take from beginning to end. Attorneys can give you an estimation of the time period for termination of marriage. But always remember that this is an estimated time only and there may be delay also in your case to get the order.

Well, the time required to get the final order from the court depends on a lot of things such as the nature of the case; the parties; the county where you file your papers; the judge; the state; and so many variables.

Here are some important points that determine the time period for the final order:

• In some of the US states there is the requirement of separation or waiting period and only after the completion of waiting period, a judge can give a final order.
• Also most courts in the US state will not issue a final decree until all division of property and all child custody issues have been resolved.
• If the divorce is uncontested it will take less time as compared to a contested one.The time for an uncontested divorce will depend on the Court and the judge and even the nature of the action.
• As per the US divorce statistics uncontested cases generally take about three to six months from the date of filing.
• Also according to the statistics contested cases generally take about nine months to a year from the date of filing.
• In a divorce case where child custody, division of assets and property or other issues are involved, it will take more time. This is because you need time to complete the paperwork and the judge will also take time to review the papers to make sure they comply with the applicable laws.
• In some of the US states, you need to fulfill the residency requirements to file a petition. For instance, in California it is must to fulfill the residency requirements of one party living in the state for at least six months and  at least three months in the state you are filing the petition. 
• Uncontested cases where both parties agree on the community property/debt, a parenting plan, child support, etc., the divorce can become final quickly as there is no need of any court hearings. Here uncontested paperwork, signed by both parties, is submitted to the judge’s office and the final order is granted by the judge.
• In a contested cases, parties usually do not agree on certain issues like community property/debt, a parenting plan and so on. This is why such cases take longer time. The exact time depends on how many hearings must be held to settle the contested issues.
• In most of the US states, in contested cases, the couples need to serve a waiting period after filing for a divorce before it may be granted. The waiting period in most of the US states is of 60 to 90 days. When the waiting period is about to be over, the final hearing date is decided by the court.
• In uncontested cases with children, the parents are required to take two classes: the Divorce Orientation class and the Divorce Education for Parents Class. After completing these classes only, final order is given by the court.

Cooperation can help in faster divorce:

Cooperation between both parties and a commitment to resolve legal issues together can help in getting the order fast from the court. Without cooperation, a divorce case may even take several years before a final order is declared by the judge. The more cooperative the parties are, the lesser will be the time peirod for final order.

To conclude, there is not an exact answer regarding how much time it will take to dissolve a marriage. However, depending upon the complexities and simplicity of a case along with the state of residence, it may go a little faster and at times it may take much longer. No matter what three to five months can be considered a normal time period to get a divorce in the USA.