Can I still marry although my visa has run out?

You may still marry. If you intend to remain in the US your wife should petition for you as soon as possible after the marriage, as you will then be out of status and subject to being taken into custody and removed from the US.

It is fine. You can get married even after your visa runs out as long as you entered the US lawfully and can prove that lawful entry. After the marriage you can apply for adjustment of status to permanent residence on the basis of the valid marriage to a US citizen. Please let me know if you have any additional questions or how I can be of further assistance to you in this matter.

Yes, you can still marry your US citizen girlfriend right here in the United States even after your B-2 visa has expired. Should you so desire, your then US citizen wife can file a Form I-130 petition for you concurrently with a Form I-485 Adjustment of status application[ green card]. Done properly, you should get a green card within 6 months or so of filing the applications. Please note that in filing for these applications some other issues bearing on your eligibility to get a green card might come up which is not addressed in your question or the response to it. I suggest you consult in detail with an experienced immigration attorney

You may get married at any time regardless of your immigration. You can apply for a green card afterwards even if your current immigration status expired as long as your spouse is a U.S. citizen.

I guess that you intend to stay in the U.S. with your wife and are concerned that USCIS will give you hard time for overstaying your visa. Don't be: if you entered the U.S. on a visa, and were inspected and admitted, a visa overstay or another violation of your non-immigrant status (for instance, accepting employment without authorization) do not disqualify you from receiving a green card as a husband of a U.S. citizen who filed an immigrant petition for you. In other words, it's okay to have a wedding 2 weeks (or even a couple of years) after your authorized stay ends. There are three scenarios you should be careful to avoid: A. If you leave the U.S. after your visa status expires and before receiving your green card, it will be very difficult to get back in. B. If, after your visa status expires and before you receive a green card, US Immigration & Customs Enforcement (ICE) arrests you, it will be very hard to convince them not to deport you. C. If a state police arrests you for breaking the law, they will call ICE to come get you; besides, even a minor criminal conviction often means disqualification from eligibility for a green card. So, don't leave the country, and don't get arrested. Or you might consider getting married now. After all, being pronounced a husband and wife by an authorized public servant is all that's needed for your wife to petition the government for your immigrant visa. The process will take quite a few months; and, before having to attend the interview with a USCIS officer, you will have plenty of time to have your wedding ceremony in September. This way, you can avoid falling out of status and cut down the time you would have to wait for permission to work in the U.S. (as well as permissions to drive, open bank accounts, travel abroad, and breathe without looking over your shoulder). So, it might be well worth considering. Just make sure that the registration of your marriage occurs not sooner than on 91st day after your entry into the U.S.

Well, theoretically you probably may. However, you run into the problem of your marriage petition being rejected by the USCIS, you will be in violation of admission laws of the code with all ramifications following this violation. Also, I suggest you check if your girlfriend will be able to file for you affidavit of support with sufficient income.

Yes, if you are not picked up by Immigration before the marriage.

You can marry after the expiration date and still apply for the green card. No penalty in overstaying either. If done correctly, the entire process should take 90 days. And you must remain in the U.S. during this process.

There is no law against marrying someone. If you are concerned about getting a greencard and remaining in the U.S., you can do it if you are marrying a U.S. Citizen if other conditions are met and no fraud is involved. Please consult with an Immigration Attorney who will walk you through the process, insure that you will not have any problems and help you with the legal paper work.

Usually when a person enters the U.S. with inspection and they get married to a U.S. citizen, they can apply for Adjustment of Status ("Greencard"), even if they are no longer in status (i.e., their visa has expired) (There is an except to this rule for people who enter the U.S. on a Visa Waiver Program, but this doesn't apply to you). So yes, since you entered the U.S. on a B2 visa, you will be eligible to apply for adjustment of status after you get married to your U.S. citizen girlfriend. Once you file your adjustment application, you will be authorized to stay in the U.S. even without your B2 status, until your application is approved and you receive your Greencard.