Which one is a bigger niche?

Depends on the services your offering..
but I'd say 1,2,4

You would likely get some good answers if you asked this in the "Offline Marketing Discussions" section. There are some experts that pop in there often.

2 and 4

The correct answer takes your location into account. If you are in middle America, I would say Churches. If you are in Florida, you want to target nightlife.

For SMS marketing, I think 1 and 2 can be the best choice for you.

Bars and restaurants are the biggest. However, if you expect these businesses to do their own messaging, that may be a problem. Some like being hands on while others prefer to have it all done for them.

Take this to the offline section for experienced answers.

Restaurants. They usually see the best results from SMS campaigns.

The best way to look at these markets is not necessarily by size but by the speed and easy with which you can penetrate the markets. Generally this is driven by your knowledge of a specific market and the relationships you have within each market.

They all represent good sized markets, but the questions to ask are:

1) Which markets can I most easily reach the decision maker. Time is money, so closing sales quickly will provide confidence and momentum to approach more clients and close more deals. Success begets success.

2) Who do I know and what markets do I have personal/business relationships with? People like to do business with people they like. It makes the credibility easier to establish.

3) Consider approaching people you know in these markets to 'get their opinion and advice' about your services... not to sell to them. Avoid asking them for the order so they are not in a position to tell you no. If they are interested in what you are offering, they will let you know. If not, ask if they know someone you can talk with that may have an interest in your services. Don't sell TO your relationship, sell THROUGH them to their network of contacts.

Hope this is helpful.

None of these are niches, but there are far more restaurants than the other categories combined.

RoD