 Blessed Aaron, O.P. |
 Saint Aaron |
| Saint Aaron |
 Saint Abaco |
 Saint Abbon de Fleury, O.S.B. |
| Saint Abbondio |
| Saint Abbondio Layperson. Companion of Saint Ireneo. Buried in Cemetery of San Lorenzo on Via Tiburtina. Martyr. |
 Saint ’Abd-al-Mu’tī Masābkī (Maronite Rite) Abdel Mooti Massabki (Italiano) |
 Saint Abdas of Kaskar (Chaldean Rite) |
| Saint Abdjesus of Kaskar (Chaldean Rite) Deacon. Companion of Saint Abdas of Kaskar. Martyr. |
| Saint Abdon |
 Blessed Abdón, F.M.S. Luis Iglesias Bañuelos (secular name) |
| Blessed Abel, O.P. |
| Blessed Abelardo García Palacios, C.M.F. |
 Saint Abibus of Edessa Habibus (latine) |
| Blessed Abilio de la Cruz, C.P. Abilio Ramos y Ramos (secular name) |
| Blessed Abilio Sáiz López, O.P. |
 Saint Abo of Tblisi Layperson. Muslim convert. Martyr. |
| Blessed Abraham, O.P. |
| Saint Abraham |
| Saint Abraham d’Auvergne |
| Saint Abraham of Arbil |
| Saint Abraham of Kidunja |
 Saint Abraham of Persia |
| Saint Absalon of Caesarea |
| Saint Abudimus of Bozcaada |
| Saint Abundio de Córdoba |
| Saint Abundius Layperson. Sacristan of the church of Saint Peter. |
| Blessed Abundo Martín Rodríguez, M.S.C. |
| Blessed Acacio María, S.P. ad V. Acacio Calleja Santamaría (secular name) |
| Saint Acatius of Miletus Layperson. Bishop?. Martyr. |
| Saint Acatius of Prusa |
 Saint Accursio, O.F.M. |
 Saint Achilles Kiwanuka Achileo (Kiswahili) |
 Blessed Achilles, O.F.M. Conv. Józef Puchała (secular name) |
| Saint Achilleus Achilleo |
| Saint Acindynus |
| Saint Acisclo |
| Blessed Acisclo Juan Carmona López Born:1871.11.17 (Dos Torres, Córdoba, Spain)Ordained Priest:1895Died:1936.10.02 🩸 (Belmez, Córdoba, Spain † 64)Beatified:2021.10.16 (Córdoba, Córdoba, Spain)Priest of Córdoba. Martyr. |
| Saint Aconzio |
| Saint Acuzio |
 Saint Acyllinus |
| Saint Ada du Mans, O.S.B. Adreilde (Italiano) |
 Saint Adalar von Erfurt |
| Saint Adalard de Corbie |
 Saint Adalbert, O.S.B. Vojtech |
| Blessed Adalberto Juan, F.S.C. Vicente Angulo García (secular name) |
| Blessed Adalberto María, O. Carm. Adalberto Vicente y Vicente (secular name) |
 Saint Adalrich von Schwaben Priest. Monk of Monastery of Einsiedeln. |
 Blessed Adam Arakawa アダム 荒川 (日本語)Layperson of Fukuoka. Married. Catechist. Martyr. |
| Blessed Adam Bargielski Born:1903.01.07 (Kalinowo, Podlaskie, Poland)Ordained Priest:1929.02.24Died:1942.09.08 🩸 (KZ Dachau, Oberbayern, Germany † 39)Beatified:1999.06.13 (Warszawa, Poland)Feast:09.08Priest of Łomża. Martyr. |
| Saint Adamo di Fermo Abbot. Abbot of San Savino Monastery in Marche. |
| Saint Adautto |
| Saint Adélaïde de Bourgogne Adelheid von Burgund (Deutsch)Empress of Holy Roman Empire. |
| Saint Adelaide of Vilich, O.S.B. Adelheid von Vilich |
 Saint Adelbert van Egmond |
| Blessed Adelfa Soro Bo, O.P. |
| Saint Adeline de Mortain |
| Saint Adelphe de Remiremont |
| Saint Adeltrude d’Aurillac |
| Saint Adérald de Troyes |
 Blessed Adilio Daronch |
| Saint Adiuto, O.F.M. |
| Saint Adjutor de Vernon Religious. Norman knight and crusader. Monk of Tiron. |
| Blessed Adolfo Bonifacio Camacho Caballero Born:1881.09.27 (Castuera, Badajoz, Spain)Ordained Priest:1907.05.25Died:1936.07.25 🩸 (Castuera, Badajoz, Spain † 54)Beatified:2021.10.16 (Córdoba, Córdoba, Spain)Priest of Córdoba. Martyr. |
| Saint Adolfo de Córdoba |
| Blessed Adolfo de Esteban Rada, C.M.F. |
| Blessed Adolfo Jaime, F.S.C. Antonio Serra Hortal (secular name) |
| Blessed Adolfo Mariano, F.S.C. Mariano Anel Andreu (secular name) |
| Blessed Adolfo Martínez Sáez Born:1906.07.23 (Alhabia, Almería, Spain)Died:1936.09.26 🩸 (Pozo de Cantavieja, Tahal, Almería, Spain † 30)Beatified:2017.03.25 (Almería, Spain)Layperson of Almería. Married. Martyr. |
| Blessed Adolph Kolping |
| Saint Adolphus Mukasa Ludigo Adolofu (Kiswahili) |
| Blessed Adrian Fortescue Layperson of London. Married. Martyr. |
| Saint Adrian III Born: (Roma, Italy)Ordained Priest:Consecrated Bishop:Elected as Supreme Pontiff:884.05.17Died:885.08 (Modena, Italy)Canonised:1891.06.10 (equipollently)Feast:07.08Supreme Pontiff (884.05.17 – 885.08)Pope. |
| Blessed Adrián, F.M.S. Manuel Llop Plana (secular name) |
 Saint Adrian of Batanea |
 Saint Adrian of Canterbury, O.S.B. |
| Saint Adrian of Nicomedia Layperson. Husband of Natalia. Martyr. |
| Blessed Adriana Morales Solís Born:1880 (Puente Gentil, Córdoba, Spain)Died:1936.07.27 🩸 (Puente Genil, Córdoba, Spain † 55)Beatified:2021.10.16 (Córdoba, Córdoba, Spain)Layperson of Córdoba. Martyr. |
| Saint Adrianus van Hilvarenbeek, O. Praem. Adriaan (Nederlands) |
 Saint Adrion of Alexandria |
| Saint Aedesius of Alexandria |
| Saint Ælflæda |
| Saint Aelred of Rievaulx, O. Cist. |
| Saint Æthelberht of Kent |
| Saint Æthelburh de Faremoutiers, O.S.B. |
| Saint Æthelburh of Barking, O.S.B. |
 Blessed Afonso Pacheco, S.J. |
| Saint Afra von Augsburg |
| Saint Africanus |