Illinois

Denominational Groups, 2000

1,279,050	1,177,187	92,297	3,874,933	443,633	5,552,193
Evangelical Protestant	Mainline Protestant	Orthodox	Catholic	Other	Unclaimed

Congregational "adherents" include all full members, their children, and others who regularly attend services. The historically African American denominations are not included in the 2000 congregation and membership totals. Many are also missing in 1990 and most historically African American denominations are missing in the 1980 reports.
[More information on the data sources]

Reports

Religious Bodies	Theology	Congregations	Adherents	% Change
Catholic Church	Catholic	-109	+274,228	8.0%
Jewish Estimate	Other Theology	+93	+223,969	487.0%
Independent, Non-Charismatic Churches	Evangelical Protestant	+47	+50,545	n.a.
Southern Baptist Convention	Evangelical Protestant	+93	+41,526	16.0%
Greek Orthodox Archdiocese of America	Orthodox	+35	+36,801	n.a.
Assemblies of God	Evangelical Protestant	+45	+34,231	55.0%
Christian Churches and Churches of Christ	Evangelical Protestant	+52	+23,662	21.0%
Apostolic Catholic Assyrian Church of the East, North American Dioceses	Orthodox	+4	+22,785	n.a.
Evangelical Free Church of America, The	Evangelical Protestant	+59	+17,752	152.0%
Church of Jesus Christ of Latter-day Saints, The	Other Theology	+54	+12,249	52.0%
Independent, Charismatic Churches	Evangelical Protestant	+17	+11,398	n.a.
Apostolic Christian Church of America, Inc.	Evangelical Protestant	+19	+9,812	n.a.
Seventh-day Adventist Church	Evangelical Protestant	+34	+7,470	42.0%
Presbyterian Church in America	Evangelical Protestant	+32	+7,266	557.0%
Wesleyan Church, The	Evangelical Protestant	+28	+6,961	n.a.
Church of God (Cleveland, Tennessee)	Evangelical Protestant	-12	+5,905	48.0%
Churches of God, General Conference	Evangelical Protestant	+27	+4,413	n.a.
National Association of Free Will Baptists	Evangelical Protestant	+41	+4,351	n.a.
Association of Free Lutheran Congregations, The	Evangelical Protestant	+14	+3,807	2505.0%
Orthodox Church in America: Territorial Dioceses	Orthodox	+11	+3,428	n.a.
Baptist General Conference	Evangelical Protestant	+10	+3,052	19.0%
Christian and Missionary Alliance, The	Evangelical Protestant	+25	+3,022	94.0%
Orthodox Church in America: Romanian Orthodox Episcopate of America	Orthodox	+2	+3,000	n.a.
Evangelical Covenant Church, The	Evangelical Protestant	+7	+2,677	18.0%
Pentecostal Church of God	Evangelical Protestant	+25	+2,460	n.a.
Christian Reformed Church in North America	Evangelical Protestant	+4	+2,233	13.0%
International Church of the Foursquare Gospel	Evangelical Protestant	+27	+1,662	18.0%
Ukrainian Orthodox Church of the USA	Orthodox	+3	+1,388	408.0%
Evangelical Mennonite Church	Evangelical Protestant	+6	+1,322	118.0%
Church of God of Prophecy	Evangelical Protestant	+21	+1,118	n.a.
Missionary Church, The	Evangelical Protestant	-3	+956	43.0%
Armenian Apostolic Church / Catholicossate of Cilicia	Orthodox	0	+844	146.0%
Conservative Congregational Christian Conference	Evangelical Protestant	+4	+772	56.0%
Evangelical Presbyterian Church	Evangelical Protestant	+4	+694	n.a.
Salvation Army, The	Evangelical Protestant	+4	+452	2.0%
Orthodox Presbyterian Church, The	Evangelical Protestant	+5	+440	120.0%
Old Order Amish Church	Evangelical Protestant	+22	+417	22.0%
American Carpatho-Russian Orthodox Greek Catholic Church	Orthodox	+2	+414	n.a.
American Baptist Association, The	Evangelical Protestant	+11	+346	43.0%
Baptist Missionary Association of America	Evangelical Protestant	+3	+326	37.0%
Eastern Pennsylvania Mennonite Church	Evangelical Protestant	+3	+286	n.a.
Albanian Orthodox Diocese of America	Orthodox	+1	+270	n.a.
Apostolic Christian Churches (Nazarene)	Evangelical Protestant	0	+267	92.0%
Protestant Reformed Churches in America	Evangelical Protestant	+2	+219	50.0%
Beachy Amish Mennonite Churches	Evangelical Protestant	+3	+185	102.0%
International Pentecostal Holiness Church	Evangelical Protestant	+2	+111	99.0%
Cumberland Presbyterian Church	Evangelical Protestant	-2	+90	3.0%
National Association of Congregational Christian Churches	Mainline Protestant	0	+65	1.0%
Church of God General Conference	Evangelical Protestant	+2	+33	4.0%
Netherlands Reformed Congregations	Evangelical Protestant	+1	+31	n.a.
Allegheny Wesleyan Methodist Connection	Evangelical Protestant	+1	+18	n.a.
Friends (Quakers)	Mainline Protestant	0	+17	1.0%
Separate Baptists in Christ	Evangelical Protestant	+1	+1	0.0%
Brethren In Christ Church	Evangelical Protestant	0	-10	-14.0%
Mennonite Brethren Churches, U.S. Conference of	Evangelical Protestant	0	-35	-71.0%
Primitive Methodist Church in the USA	Evangelical Protestant	0	-133	-69.0%
Moravian Church in America--Northern Province	Mainline Protestant	0	-170	-36.0%
Brethren Church, The (Ashland, Ohio)	Evangelical Protestant	0	-287	-36.0%
Wisconsin Evangelical Lutheran Synod	Evangelical Protestant	0	-369	-4.0%
Universal Fellowship of Metropolitan Community Churches	Mainline Protestant	+4	-441	-55.0%
Syrian Orthodox Church of Antioch	Orthodox	-1	-575	-68.0%
North American Baptist Conference	Evangelical Protestant	-3	-627	-24.0%
Church of the Brethren	Evangelical Protestant	+3	-1,030	-14.0%
Unitarian Universalist Association of Congregations	Other Theology	-2	-1,983	-22.0%
Churches of Christ	Evangelical Protestant	-12	-2,299	-7.0%
Conservative Baptist Association of America	Evangelical Protestant	-4	-2,414	-24.0%
Reformed Church in America	Mainline Protestant	-1	-3,352	-16.0%
Church of the Nazarene	Evangelical Protestant	-10	-10,627	-22.0%
Free Methodist Church of North America	Evangelical Protestant	-7	-11,417	-66.0%
Church of God (Anderson, Indiana)	Evangelical Protestant	-9	-16,615	-62.0%
American Baptist Churches in the USA	Mainline Protestant	-2	-16,653	-16.0%
Christian Church (Disciples of Christ)	Mainline Protestant	-34	-16,841	-23.0%
Episcopal Church	Mainline Protestant	-6	-21,266	-29.0%
United Church of Christ	Mainline Protestant	-33	-24,728	-13.0%
Lutheran Church--Missouri Synod	Evangelical Protestant	+15	-35,417	-11.0%
Evangelical Lutheran Church in America	Mainline Protestant	-20	-39,828	-12.0%
Presbyterian Church (U.S.A.)	Mainline Protestant	-44	-60,062	-31.0%
United Methodist Church, The	Mainline Protestant	-146	-140,224	-28.0%
	Totals:	468	+424,344	+6.8%

The population of these 102 counties (or equivalents) in 1980 was 11,426,518; in 2000 it was 12,419,293. The total population changed 8.6%. The adherent totals for 1980 (6,250,249) represent 54.7% of the 1980 population. The adherent totals for 2000 (6,867,100) include 55.3% of the 2000 population. There is sufficient data for 78 groups to calculate 1980-2000 change. These 78 groups had 6,219,118 adherents in 1980 and 6,643,462 adherents in 2000, for a change of 6.8%

Sources

The 2000 data were collected by the Association of Statisticians of American Religious Bodies (ASARB) and includes statistics for 149 religious groups, including number of churches and adherents. Dale E. Jones, Sherri Doty, Clifford Grammich, James E. Horsch, Richard Houseal, Mac Lynn, John P. Marcum, Kenneth M. Sanchagrin and Richard H. Taylor supervised the collection. These data originally appeared in Religious Congregations & Membership in the United States, 2000, published by the Glenmary Research Center.

The 1980 data were collected by the Glenmary Research Center and include statistics for 111 Judeo-Christian church bodies, including number of churches and adherents. Bernard Quinn, Herman Anderson, Martin Bradley, Paul Goetting and Peggy Shriver supervised the collection. These data originally appeared in Churches and Church Membership in the United States, 1980, published by the Glenmary Research Center.

[More information on these data sources]