May 1 edit
Achatius; Ache; Acheolus; Acheul; Achius & Acheolus; Aehgein of Fore; Brioc; James the Just; Saint Joseph; Peregrine Laziosi; Philip the Apostle; Ultan of Ardbraccan; Philip and James, Apostles;
May 2 edit
Achumdemas; Aedhan McCuamsie; Athanasius of Alexandria; Mafalda of Portugal;
May 3 edit
Abhai (saint); Abhai the Bishop; Aedhan; Pope Alexander I; Finding of the Cross; Philip the Apostle and James the Less; Shmouni & her sons; Theodosius of Kiev;
May 4 edit
Ada; Adrechildis; Agilbert of Angers; English Saints and Martyrs of the Reformation Era; Saint Florian; Gotthard of Hildesheim; Saint Pelagia;
May 5 edit
Abraham (Ethiopian); Adrianus Monsenski; Ascension; Hilary of Arles; Jutta of Kulmsee; Pope Pius V;
May 6 edit
Ache; John the Evangelist;
May 7 edit
Achatius of the Haptascalon; Achatius the Centurion; Agathius the Centurion; John of Beverley; Nil Sorsky; Stanislaus of Szczepanów;
May 8 edit
Achatius the Centurion; Agathius the Centurion; Arsenius the Great; Pope Benedict II; Julian of Norwich; Peter of Tarentaise; Victor of Milan;
May 9 edit
May 10 edit
Achates; Achatius; Achatius the Centurion; Aedh of Kildare; Agathius the Centurion; Antoninus of Florence; John of Avila; Simon the Zealot;
May 11 edit
Abgar V of Edessa; Achilles, Sipponius, Epimenus & Nereus; Achius and Acheolus; Adalgar of Hamburg; Adger; Aelgnei; Agathander; Agathimber of Metz; Comgall; Saint Cyril; Saints Cyril and Methodius; Saint Methodius;
May 12 edit
Achaicus; Achilleus; Epiphanius of Salamis; Florence Nightingale; Patriarch Germanus I of Constantinople;
May 13 edit
Abban the Hermit; Ager; Agnes and Disciola; Agrippa; Agrippa; Andrew Hubert Fournet; Julian of Norwich; Robert Bellarmine;
May 14 edit
Adauctus; Addaeus; Addai; Adeltrudis; Adeodatus; Aegydius Valledaris; Afranus; Aglae; Agrippa; Magdalen of Canossa; Maria Mazzarello; Saint Matthias; Michael Garicoïts; Pachomius;
May 15 edit
Achilles of Larissa; Achillius of Larissa; Adalsindis; Jean-Baptiste de la Salle; Pachomius; Pentecost; Virgin Mary;
May 16 edit
Aaron (Copt); Aba of Kaskhar; Abda, Abdallah, Abdias, Abdjesus; Abdjesus; Abdjesus of Kashkar; Abdha; Abercius and Helena; Abraham; Brendan; Caroline Chisholm; John of Nepomuk; Maris, Martha, Abachum and Audifax; Simon Stock;
May 17 edit
Adrion, Victor & Basilla; Aemilianus of Vercelli; Agapius; Agathocles; Agrippina; Robert Bellarmine;
May 18 edit
Aelgyfa; Aghna; Elgifa; Eric IX of Sweden;
May 19 edit
Aemilius, Basilius, Praetextata, Basia & Partinus; Agrippa; Agrippa and Laurentius; Pope Celestine V; Dunstan; Helena of Constantinople; Ivo of Kermartin;
May 20 edit
Abercius and Helena; Alcuin; Bernardino of Siena; Friday of Gold; Ivo of Chartres; Æthelberht II of East Anglia;
May 21 edit
Abraham of Egypt; Adalric; Adelphius; Adrianus; Agapitus Markushewski; Agapius of Caesarea; Agathodaemon; Agathus; Helena of Constantinople;
May 22 edit
Aderald; Aemilius & Castus; Aghna, Luidhsech, & Caissin; Joachim de Mas y de Vedruna;
May 23 edit
May 24 edit
Afra; Aftze; Agrippina and Lauriana; Charles Wesley; John Wesley; Lanfranc; Vincent of Lerins;
May 25 edit
Aldhelm, Bishop of Sherborne; Bede; Pope Boniface IV; Pope Gregory VII; Madeleine Sophie Barat;
May 26 edit
Augustine of Canterbury; Pope Eleutherius; John Calvin; Philip Neri; Quadratus of Athens;
May 27 edit
Acculus; Agrius; Aquilinus; Augustine of Canterbury; Bede; Eukarius; John Charles Roper; Pope John I;
May 28 edit
Accidia; Acronius, Demonasia, Ammonius, & Menas; Adhemar; Aemilius, Felix, Primus, & Lucianus; Augustine of Canterbury; Germain of Paris; Lanfranc; Roberta Elizabeth Tilton;
May 30 edit
Ablak; Aflak; Apolo Kivebulaya; Pope Felix I; Ferdinand III of Castile; Joan of Arc; Josephine Butler;
May 31 edit
Agapia; Visitation (Christian) or Visit of Mary to Elizabeth;