Under most states' laws, your landlord can terminate your tenancy when you don't pay rent. Termination of your tenancy is not the same as eviction: When your tenancy is terminated, you receive a notice from the landlord, possibly a second chance to pay your rent, and (if you can't pay the rent or you aren't eligible for a second chance) a deadline by which you must move out. If you don't abide by the terms of the termination notice, it is then that your landlord can then begin an eviction lawsuit.
Every state requires landlords to follow certain procedures when terminating a tenancy, and state laws regarding the timing of and required content of termination notices—often called "quit" or "pay rent or quit" notices—vary greatly. You'll need to check your state's law on termination for nonpayment of rent for the specifics about:
When you receive a notice to pay rent or quit, read it carefully, and evaluate your options. Pay the rent if you can before the deadline, or contact your landlord to see if you can negotiate a payment plan or get an extension. If you're able to come to an agreement, get it in writing.
If you receive an unconditional quit notice, or you know you can't pay rent, try to move out before the deadline. Even if you move out, your landlord is still entitled to rent and late fees due. Your landlord might deduct what you owe from your security deposit, and, if the deposit isn't enough, can sue you for the remaining amount. However, moving out voluntarily is preferable to being evicted, and your landlord might decide it's not worth the effort to sue you. On the other hand, if your landlord is forced to evict you, you'll not only have an eviction judgment against you, but also possibly a judgment for rent, late fees, attorneys' fees, and court costs.
Your landlord can't evict you—that is, physically throw you and your possessions out of the rental—without a court order. To secure a court order, your landlord must follow all termination and eviction lawsuit procedures, and demonstrate at trial that you've done something wrong (like not paying the rent) that justifies eviction. If you have a defense—a reason why you shouldn't be evicted—you will be able to present it to the court. For a discussion of the eviction procedure, including time periods, negotiation strategies, and an overview of an eviction lawsuit, see Every Tenant's Legal Guide, by Janet Portman and Marcia Stewart (California residents, see California Tenants' Rights).