US immigration doesn't recognize "common law" relationships, there isn't a particular USA partnership visa

If  you are an unmarried spouse of the US passport holder or US citizen  regardless of whether you've been in long-term relationships for the  purpose of traveling

to the US you'll need to meet the requirements and apply for the visa in your own name.  There are a variety of aspects that should be considered

One  of the most important considerations is what you will do after arriving  in the US Are you traveling in America to visit your family, US for a  visit with your spouse temporarily

It  is important to note that you won't be eligible for admission to the US  visa holder spouse as a dependent if you are not married.

In order to be eligible for the spouse visa based on family spouse visa in the first place, you'd have marry.

If you're a resident of one of the visa-free state, you could be able for travel in the US for up to 90 days in order to visit your US-based friend

It is a much faster and less expensive process than visa applications.  To travel visa-free, you must first obtain an the ESTA authorization.

To  be eligible for visa-free travel you will need authorization to travel  into in the U.S. using the Electronic System for Travel Authorization  (ESTA).

It is necessary to fill out an online form to pre-register at the ESTA website. It is recommended by U.S. Customs and Border Patrol to do the form minimum 72 hours in advance of your departure.

The  majority of people will be granted authorization if you're citizens  from one of the VWP partners and have an electronic passport that is  valid and has the electronic chip

You  have been detained for a specific crime even if the arrest didn't  result in criminal conviction and you also have a criminal history

– You have been refused entry into or deported from the U.S or already been a victim of the VWP.  – You have a serious, infectious disease