Paraguay is divided into departamentos (departments), which are divided into distritos (districts). The number of districts was 190 in 1982, 219 in 1992, 224 in 2002, and 249 in 2013. The table below shows the 224 districts of Paraguay according to the census of 2002-08-28.

Atlas Censal de Paraguay  has links to pdf files with detailed maps of the districts, by department.

Change history:

The Paraguayan Chamber of Deputies had a web page for Legislation (http://www.camdip.gov.py/Principal/Legislacion/legislacion.html, dead link, retrieved 2003-07-13), with year-by-year links to lists of the laws passed from 1948 to 2000. The following timeline shows all the district changes I could find. There were probably others not listed. For the most part, I've used the spelling given in the summaries of laws. In these notes, any information about the districts that were modified to create the new districts has been inferred from the maps in the Atlas Censal de Paraguay on the DGEEC site.
1948-11-25: The division into districts of Central and Paraguarí departments was modified by Law No. 52.
1953-04-27: Tebicuarymi compañia was raised to the status of district by Law No. 155. I suppose this means that Tebicuarymi had been a subdivision of some district, but on this date it was split away from that district to become a district of its own.
1957-08-12: Capitán Miranda municipio was created by Law No. 444.
1957-08-31: Mauricio Jose Troche district split from Natalicio Talavera, Guairá, by Law No. 457.
1957-09-12: Status of Capitán Miranda changed from municipio to district by Law No. 468 (my interpretation; a literal translation would read, "Law No. 468: by which Law No. 444 of August 12, 1957 is modified (which creates the district of Capitán Miranda)").
1960-06-10: Bella Vista del Alto Paraná colonia (in Itapúa department) was raised to the status of district by Law No. 589.
1960-10-04: Abay compañia (in Caazapá department) was raised to the status of district by Law No. 690.
1961-05-05: Jose Fassardi district split from General Eugenio A. Garay, Guairá, by Law No. 696.
1961-08-30: Capitán Vicente Antonia Matiauda district (in Itapúa department) was created by Law No. 721.
1962-05-18: Cecina, Rosario Pastoreo, Taruma, and Villa Pastoreo compañias were transferred from Jose Fassardi district to Abai district by Law No. 774.
1962-06-05: Lambaré district created by Law No. 791.
1962-07-31: Puerto Pinasco district created by Law No. 818.
1964-06-23: Name of Mayor Jose deJesus Martinez district changed to Pedro Gonzales by Law No. 930.
1966-07-05: Doctor Juan Manuel Frutos district split from Caaguazú district, Caaguazú, by Law No. 1136.
1966-08-31: Additional territory annexed to Puerto Pinasco district by Law No. 1191. Jesus and Trinidad districts created by Law No. 1193.
1967-07-17: Presidente Stroessner district created by Law No. 1251.
1968-10-30: Juan Leon Mallorquin district created by Law No. 20. Juan O'Leary district created by Law No. 21. Both districts were split from Hernandarias, Alto Paraná.
1972-07-04: Villalbín district split from Cerrito, Ñeembucú, by Law No. 354.
1972-10-14: Name of Nueva Australia district changed to Hugo Stroessner by Law No. 362.
1972-12-22: Yataity colonia was raised to the status of district and renamed Felipe Matiauda by Law No. 385.
1973-07-30: Salto del Guairá district split from Hernandarias, Alto Paraná, by Law No. 390.
1973-09-07: Loma Grande district created by Law No. 394. 25 de Diciembre colonia, formerly part of San Estanislao, San Pedro, was raised to the status of district by Law No. 396.
1973-12-07: Administrative divisions of Paraguay reorganized, at both the department and district levels, by Law No. 426. Canindeyú department formed by taking Salto del Guairá district from Alto Paraná and Curuguaty, Villa Igatimí, Ypehú districts from Caaguazú. Part of Puerto Pinasco, Boquerón, split off to form Pozo Colorado; another part transferred to Alto Paraguay and named Departamento Chaco; and the remainder transferred to Presidente Hayes under its original name. La Victoria district in Alto Paraguay formed from parts of Fuerte Olimpo, Alto Paraguay and former Puerto Pinasco, Boquerón. Yabebyry district transferred from Ñeembucú to Misiones. Other territorial changes occurred.
1973-12-21: Mbocayaty del Yhaguy district split from Caraguatay, Cordillera, by Law No. 428.
1974-11-08: Repatriación district split from Caaguazú district, Caaguazú department, by Law No. 467.
1974-11-15: Presidente Franco district, Alto Paraná, was formed from parts of Ciudad del Este and Domingo Martinez de Irala by Law No. 469.
1974-12-04: Domingo Robledo district, Itapúa, was created by Law No. 484. Salitre-Cue compañia, formerly part of San Pedro del Paraná, Itapúa, was raised to the status of district and renamed José Leandro Oviedo by Law No. 485.
1974-12-18: Corpus Christi district, Canindeyú, was split from Salto del Guairá by Law No. 497.
1976-12-09: Doctor Juan Ramon Chavez district, Caaguazú, was created by Law No. 617.
1976-12-17: La Victoria district, Alto Paraguay, was created by Law No. 619.
1978-07-18: Repatriación district expanded by Law No. 697.
1978-12-15: Itanara colonia, Canindeyú, was raised to the status of district by Law No. 723. Mayor Julio Dionisio Otaño colonia was split from Capitán Meza, Itapúa, and raised to the status of district by Law No. 724. Carlos Antonio López colonia and San Lorenzo colonia were split from Capitán Meza, merged, and raised to the status of district by Law No. 725, constituting Carlos Antonio López district. Alborada colonia, Apeaime colonia, and San Rafael colonia were split from Capitán Meza, merged, raised to the status of district, and renamed San Rafael del Paraná by Law No. 726.
1979-11-26: Presidente Franco district expanded by Law No. 776.
1979-12-24: San Pablo colonia (formerly named Cocuere), San Pedro, formerly part of San Pedro de Ycuamandiyú, was raised to the status of district by Law No. 792. Boundary was defined for Domingo Martinez de Irala district, Alto Paraná, by Law No. 794. According to the summary of this law, the district had been created by Law No. 426 on 1973-12-07.
1980-09-08: Boundary was defined for Mariscal Jose Felix Estigarribia district by Law No. 808. According to the summary of this law, the district had been created by Decree-Law No. 13501 on 1946-05-07.
1980-10-13: Yguazu colonia formed from parts of Ciudad del Este and Dr. Juan León Mallorquín, Alto Paraná, and raised to the status of district by Law No. 815.
1981-11-13: Doctor J. Eulogio Estigarribia district was created, and the boundary of Juan Manuel Frutos and Caaguazú districts, Caaguazú, was modified, by Law No. 873. This suggests that the new district may have been formed from parts of the other two.
1981-12-07: Antidia Matiauda district, Itapúa, was created by Law No. 883.
1981-12-11: Chore district, San Pedro, was split from San Estanislao by Law No. 885.
1981-12-18: General Francisco Isidoro Resquin district, San Pedro, was split from Lima by Law No. 911.
1982-11-19: Law No. 911 (see previous entry) was modified by Law No. 957, but there is no indication how.
1982-12-07: Boundary was defined for Caapucu district, Paraguarí, by Law No. 969. R.I. 3 Corrales district, Caaguazú, was split from Caaguazú district by Law No. 970.
1982-12-17: Domingo Robledo district, Itapúa, expanded by Law No. 972.
1983-08-19: Doctor Botrell district, Guairá, was split from Capitán Mauricio J. Troche by Law No. 1001.
1983-10-04: Tomas Romero Pereira district, Itapúa, was split from Edelira by Law No. 1009.
1984-12-07: San Cristobal district, Alto Paraná, was split from Domingo Martinez de Irala by Law No. 1092.
1984-12-20: Ñacunday district, Alto Paraná, was created by Law No. 1097. Yby-Yau district, Concepción, was split from Horqueta by Law No. 1100. Doña Heriberta Stroessner de Iglesias district, Itapúa, was created by Law No. 1101.
1985-10-07: Raul Arsenio Oviedo district, Caaguazú, was split from Yhú by Law No. 1143.
1985-11-15: J. Augusto Saldívar district, Central, was split from Capiatá by Law No. 1149. Law No. 428 of 1973 (above) was modified by Law No. 1153, but there is no indication how.
1986-09-01: San Jose Obrero district, Cordillera, was formed from parts of Caraguatay, Isla Pucú, Juan de Mena, and Primero de Marzo by Law No. 1202.
1986-10-03: La Paz district, Itapúa, was split from Fram by Law No. 1204.
1987-08-10: Yatytay district, Itapúa, was split from Natalio by Law No. 1244.
1987-11-30: Catuete colonia, La Paloma colonia, and Puente Kyjha colonia, formerly part of Salto del Guairá district, Canindeyú, were merged, raised to the status of a district, and renamed Francisco Caballero Alvarez by Law No. 1275. Nanawa district, Presidente Hayes, was split from Villa Hayes by Law No. 1276.
1987-12-14: Mariscal Francisco Solano Lopez district, Caaguazú, was split from Yhú by Law No. 1279.
1987-12-18: Jose Domingo Ocampos district, Caaguazú, was formed from parts of Dr. J. Eulogio Estigarribia and Dr. Juan Manuel Frutos by Law No. 1299.
1988-12-19: San Juan del Paraná district, Itapúa, was split from Encarnación by Law No. 1355.
1990-01-16: Los Cedrales district, Alto Paraná, was formed from parts of Presidente Franco and Domingo Martinez de Irala by Law No. 60.
1990-01-19: Law No. 66 restored and assigned new names to several districts of Paraguay.
1990-09-18: Boundary was defined for Capitán Meza district, Itapúa, by Decree-Law No. 20 of 1990-03-29, which was ratified by Law No. 43 on this date. Boundary was defined for Cambyreta district, Itapúa, by Law No. 45.
1990-10-09: Santa Rosa de Monday district, Alto Paraná, was split from Domingo Martinez de Irala by Law No. 63.
1991-12-26: Law No. 101 rectified the boundary of San José Obrero district.
1992-05-14: Name of Juan Ramón Chaves district, Caaguazú, changed to Santa Rosa del Mbutuy by Law No. 10.
1993-07-09: Law No. 155 of 1953 (above) was modified by Law No. 236, but there is no indication how.
1995-05-10: Name of La Victoria district changed back to the original name of Puerto Casado by Law No. 576.

Valentin Arzoumanian sent me a spreadsheet showing district mergers and splits since 1987, based on his investigations in the Gaceta Oficial de la República de Paraguay . Here are his findings, excluding duplication with the above:
1992-11-06: In Alto Paraguay department, Mayor Pablo Lagerenza district merged with Fte. Olimpo; In Boquerón department, Doctor Pedro P. Peña district merged with Mcal. Estigarribia; General Eugenio A. Garay district merged with Mcal. Estigarribia, all by Law No. 71.
1993: In Alto Paraná department, Iruña district split from Naranjal/Ñacunday by Law No. 203.
1993-07-19: In Caaguazú department, Vaquería (San Blas) district split from Yhú by Law No. 239.
1993-11-07: In San Pedro department, Capiibary district split from San Estanislao by Law No. 168.
1994: In Canindeyú department, Katueté district split from Gral. F. C. Álvarez; La Paloma (del Espíritu Santo) district split from Gral. F. C. Álvarez by Laws No. 342 and 343, respectively.
1996-08-06: In Itapúa department, Itapúa Poty district split from Alto Verá/Edelira by Law No. 926.
1998-01-08: In Presidente Hayes department, Doctor José Falcón district split from V. Hayes by Law No. 1,228.
1999-05-20: In Canindeyú department, Nueva Esperanza district split from Katueté/Sto. del Guairá by Law No. 1,430.
2001-06-06: In Presidente Hayes department, Pozo Colorado district split from V. Hayes by Law No. 1,716.
2002-06-06: In San Pedro department, Santa Rosa del Aguaray district split from Nueva Germania by Law No. 1,931.
2002-09-26: In San Pedro department, Yrybucuá/Yryvu Cua district split from San Estanislao/Capiibary by Law No. 1,989.
2002-11-01: In Canindeyú department, Yasy Cañy district split from Curuguaty by Law No. 2,005.
2003-07-11: In Alto Paraná department, Santa Fe del Paraná district split from Hernandarias/Mbaracayú by Law No. 2,180.
2005-04-25: In Alto Paraguay department, Bahía Negra district split from Fte. Olimpo by Law No. 2,563.
2006-03-21: In Presidente Hayes department, Tte. 1° Manuel Irala Fernández district split from V. Hayes by Law No. 2,873.
2006-06-09: In Boquerón department, Loma Plata district split from Mcal. Estigarribia; Filadelfia district split from Mcal. Estigarribia by Laws No. 2,927 and 2,928, respectively.
2006-09-12: In Presidente Hayes department, Tte. Esteban Martínez district split from V. Hayes by Law No. 3,000.
2008-04-21: In Guairá department, Tebicuary district split from Cnel. Martínez by Law No. 3,469.
2008-05-02: In Alto Paraguay department, Capitán Carmelo Peralta district split from Pto. Casado by Law No. 3,471.
2008-06-25: In Concepción department, San Carlos (del Apa) district split from Concepción by Law No. 3,516.
2008-12-29: In Caaguazú department, Tembiaporá district split from R.A. Oviedo by Law No. 3,421.
2009-06-20: In Presidente Hayes department, General José María Bruguez district split from V. Hayes by Law No. 3,514.
2009-12-24: In Concepción department, Azote'y district split from Horqueta by Law No. 3,960.
2011-05-26: In Alto Paraná department, Tavapy district split from Sta.Rosa del M. by Law No. 4,322.
2011-06-24: In San Pedro department, Liberación district split from Choré/Guayaibí by Law No. 4,363.
2011-09-07: In Concepción department, Sargento José Félix López district split from Concepción by Law No. 4,418.
2011-09-08: In Amambay department, Zanja Pytá/Zanja Pytã district split from P. J. Caballero by Law No. 4,417.
2011-11-16: In Caaguazú department, Nueva Toledo district split from Mcal. Fr.S. López by Law No. 4,494.
2011-12-26: In Canindeyú department, Ybyrarobaná/Ybyrarovaná district split from C.Christi/Curuguaty/Katuete by Law No. 4,571.
2012-04-19: In Caazapá department, 3 de Mayo district split from Yuty by Law No. 4,604.
2012-09-06: In Alto Paraná department, Doctor Raúl Peña district split from Naranjal by Law No. 4,725.
2013-05-30: In Concepción department, Paso Barreto district split from Concepción; San Alfredo district split from Concepción by Laws No. 4,926 and 4,927, respectively.

Other names of subdivisions:

District names are often abbreviated. Common abbreviations are Cnel. for Coronel, Dr. for Doctor, Gral. for General, and Mcal. for Mariscal. These titles may be omitted entirely.

1. Capiibary, SP: Capiivary (variant)
2. Curuguaty, CY: Villa San Isidro Curuguaty (variant)
3. Guayaibí, SP: Guajayvi (variant)
4. Itakyry, AA: Itaquyry, Ytakyry (variant)
5. La Victoria, AP: Puerto Casado (obsolete)
6. Nanawa, PH: Puerto Elsa (obsolete)
7. R. I. 3 Corrales, CG: Regimiento de Infantería 3 - Corrales (variant)
8. Santa Rosa del Mbutuy, CG: Juan Ramón Chaves (obsolete)
9. Tabai, CZ: Tavaí (variant)
10. Villa Ygatimí, CY: Igatimi, Ygatymí (variant)
11. Yabebyry, MI: Yavevyry (variant)
12. Ypejhú, CY: Ypehú (variant)