WASHINGTON — America’s health insurance marketplace closes on Monday night, the deadline for most people to obtain coverage or face a penalty.

The confusion and uncertainty of the last six months appear likely to continue as consumers, including some who have never had insurance, begin using new policies for the first time. Here are answers to some frequently asked questions.

Q. What happens if a consumer does not sign up for insurance by the Monday deadline?

A. The consumer may be subject to financial penalties, to be paid with federal income taxes next year. However, the federal government has said it will stretch the sign-up deadline for people who started an application and could not finish it for one reason or another.

To preserve their rights, consumers can call the federal insurance marketplace (1-800-318-2596) and request a “special enrollment period.”