A house church is a church that intentionally stays within the general attendance range of 10-15, so that there can be active participation, intentional evangelism and discipleship, and accountable relationships. This size of church can still meet in homes or similar places.  Growth occurs by reproducing into new house churches, rather than growing the number in one group.  House churches are sometimes described as organic church, relational church, simple church, basic church and so on.

The meeting formats vary widely, but in general, are kept simple and participative.  New leaders are raised up from within the church, using an apprentice/modeling approach.  One will rarely hear a "sermon" at a house church meeting.

While smaller and simpler than other kinds of churches, house churches are still very definitely church.  They evangelize, make disciples, worship, fellowship and minister, in obedience to biblical mandates.  They are made up of baptized believers.  They are self-sustaining, self-governing, and reproducing. 

It costs nothing to start a house church.  It does not require a highly trained leader to start a house church.  A house church can be started almost anywhere.  The only thing that limits planting and reproduction of house churches is willing obedience.

Whenever a person has just become a new believer, those who are discipling that person help them to prepare their personal testimony, and identify those in their relationship network (family, friends, neighbors, fellow workers/students, fun friends) who are not in church, and then invite them into their home for the beginnings of a new house church.  Every new believer offers this same potential.  So, a house church with 10 lost persons, could become 10 new house churches as each individual is saved.  As this kind of expansion continues, house churches can reach very large numbers of lost people in a short period of time.

Most often, up to 10 or so house churches choose to network with one another, and gather for joint, celebrative worship about once a month.  These joint, celebrative worships are normally held in rented school facilities, community halls, hotel banquet rooms, or other such locations.  Often, the network will become legally organized and take care of financial transactions and reporting, rather than each individual house church doing so.