I think it depends on what your goal is:). 

Personal time 

Networking time 

Ad creation time 

Analytics time 

FB live streaming time 

FB Group building time 

FB fan building time 

etc, etc, etc 

There i s not enough time in a day to do you can do on social media, So much to do, so little time. 

I trained one of my VAs to manage my tweets in Hootsuite for me, Hootsuite is great for automating the tweets but is still needs a human to input the tweets and also to reply to people and thank people, etc. 

I train another one to help with postings. I also use CityBlast for posting. But still I must say I spend anywhere from one hour to five hours, and sometimes more on social media, depending on the tasks, etc. 

About an hour total on the average. Some days more some days less. 

It depends upon your objectives and interests.

It depends on your business plan and how you are using social media to increase your business. I'd take a 30 day study of it; measure the time spent vs. results gotten. The data reveals your answer.

Depends on what you are trying to accomplish. I've started using posting software that is helping tremendously. Sometimes it takes an hour to just post to AR if it is acting up!

as spend as much time as possible.... I market for the "top dogs" in the area...

Depends on how much time you have - I spend less than 1 hour a day sometimes less when I hand it over to my webmaster

60-90 minutes

2 hours gets a good job done.

Totally up to the individual.

Personally, I'd like to say that zero time is reasonable. I have never particularly cared for social media. But once it goes over 60-90 minutes it's excessive to my way of thinking unless you get the majority of your leads from social media.

As my schedule allows, start with 1 hour as my eyes and fingers start to work normally

Donna Foerster An hour in the morning and I usually check again in the evening.

I have no idea.  I think one should determine what works for them.

I spend from 1 to 3 hours a day depending on all the factors that Nestor & Katerina Gasset identified.

Do you do this for a living? If so, it's an all day thing. If not, weigh the cost of hiring someone.

Usually, 1 sale a month will over the cost of a good webmaster to do this for you and should bring in enough business to cover their expense and more.

It's a personal choice, I spend enough time as needed to do what I need to do and then get back to the next task and prioritize as well.    

It totally depends on the goals. If it's just a swing through facebook to keep in touch with friends and family, the answer will be totally different than if it's writing and distributing posts and making videos, uploading photos, etc.

Katerina Nestor & Katerina Gasset answers this question very well in my opinion.

Donna depends how productive you are with it, for me certain sites very little time others a lot more. Some sites I do not even go on every other day. It also depends how busy I am with my Real Work that is Real Estate, Endre

Never on "prime time", only once I have a little down time, Then it actually becomes relaxing yet is productive. Being on the Internet, I believe, becomes habit forming that makes us believe we are productive. But are we? Yes, how much is too much? The answer, what kind of business are you getting out of it?

I spend a good portion of my day on Social Media. It is how I get business.

I'm actually on social media in the a.m. and in the p.m., as once a day is just not enough.  That includes AR and FB Donna Foerster.  If I have a wide span of time I stay on longer, but that is not always the case! 

I spend much less time now days - about one hour, and have many more hitting my web site.

I check all in the morning, about 15 min for each, and afternoon for the same time. When I receive a direct message, I try to answer immediately. 

12 minutes on Facebook. Even though AR is social media, not the category I use to justify it.

1-2 hours, mostly on AR.

If you try to regulate or control it has one affect. If you go with the flow another...Find your center...each one should find their own comfortable shoe

It depends if you are posting pictures of your lunch and pet, as opposed to promoting your services.

Varies, but usually less than a hour!

About an hour each day and if ot on the boat a lot less!

What is reasonable may differ from one to another. With the exception of last week, For me it is what time i put aside in the morning to post a blog and interact. I think of Active Rain as an investment that does bring about new business as opposed to going on the time of Social media that is More   than business. 

What is reasonable is a personal decision. Many of us spend too much time on social media.

It depends on how much time I have.

My personal habit is twice a day, each time for 10-15 minutes. 

It depends on what you're working on. 1-3 hours seems common.

It varies with my goals for the week. Usually 30-60 minutes/day.

Not sure there is an average. Depends on your goals and what sites you are on.

Donna Foerster - one survey said... 15 minutes (3 sessions of 5 minutes each.)

2 - 3 hours daily.  Not all at once.  Sometimes in the evenings I can sit for a couple extra hours on social media.  

2 hours max.

I think it is different for different people, but some people do seem to get obsessed with it.

Depends on how effective you are and what your goals are.

I spend 90 minutes per day for all of my social media.

I was about to say exactly what Marc Swartz, CPA, CA, Real Estate Broker said.

It is probably a necessary evil. Rather getting a lead, I think I will soon go to funeral home to pay my respect.