Often people sense a call of God to ministry.
In response to the call they find themselves not knowing whether to start a church or a ministry.
The best way to approach this question is to consider the differences between the two:
A Church is a well structured organization defined in scripture regarding its protocol and governance. In other words, a church must have pastor(s), elder(s), deacon(s), etc.
However, a ministry is much more flexible. It is only governed by the principles of Christianity without the protocols of a church. It may or may not have pastor(s), elder(s), deacon(s), etc.
It should be noted that one is not better than the other. However, one may be a better fit to the minister who has decided to answer their call.
Application by Example:
Let’s say that a divorced woman believes that she is called to be a pastor.
In some Christian circles she will have two strikes against her:
1) she is a woman, and
2) she is divorced.
If she feels that she must interact with people who hold these prejudices, it may be her to advantage to start a “ministry”. Then if someone attempts to invalidate her role as a pastor, she can remind them that the Bible does not define the office of a pastor over a ministry –as opposed to a church.