How to Gain Indulgences
...when I am gone pray for the repose of my soul.
(St. Monica)
The source for this material is the Enchiridion Indulgentiarum (Handbook of Indulgences)
issued by the Sacred Apostolic Penitentiary of the Roman Catholic Church in 1968. It replaced the previous volume, the Raccolta.
This is a detailed page with selected passages: refer to the Handbook itself for additional reference.
Norms on Indulgences
5. The grant of a partial indulgence is designated only with the words "partial indulgence," without any determination of days or years.
6. The faithful, who at least with contrite heart perform an action to which a partial indulgence is attached, obtain, in addition to the remission of temporal punishment acquired by the action itself, an equal remission of punishment through the intervention of the Church.
18. A visit to a church or oratory, if required to gain an indulgence attached to a certain day, can be made from noon of the preceding day to midnight at the close of the day itself.
19. The faithful, who devoutly use an article of devotion (crucifix or cross, rosary, scapular or medal) properly blessed by any priest, obtain a partial indulgence.
But if the article of devotion has been blessed by the Sovereign Pontiff or by any Bishop, the faithful, using it devoutly, can also gain a plenary indulgence on the feast of the Holy Apostles, Peter and Paul, provided they also make a profession of faith according to any legitimate formula.
20-2. An indulgence attached to the use of an article of devotion only ceases, when the article is completely destroyed or is sold.
22-1. To be capable of gaining an indulgence for oneself, it is required that one be baptized, not excommunicated, in the state of grace at least at the completion of the prescribed works, and a subject of the one granting the indulgence.
22-2. In order that one who is capable may actually gain indulgences, one must have at least a general intention to gain them and must in accordance with the tenor of the grant perform the enjoined works at the time and in the manner prescribed.
24-1. A plenary indulgence can be acquired once only in the course of a day.
24-2. But one can obtain the plenary indulgence for the moment of death, even if another plenary indulgence had already been acquired on the same day.
24-3. A partial indulgence can be acquired more than once a day, unless otherwise expressly indicated.
25. The work prescribed for acquiring a plenary indulgence connected with a church or oratory consists in a devout visit and the recitation during the visit of one Our Father and the Creed.

(Details on Plenary Indulgences)
26. To acquire a plenary indulgence it is necessary to perform the work to which the indulgence is attached and to fulfill the following three conditions: sacramental confession, eucharistic Communion, and prayer for the intention of the Sovereign Pontiff. It is further required that all attachment to sin, even venial sin. be absent.
If the latter disposition is in any way less than perfect or if the prescribed three conditions are not fulfilled, the indulgence will be partial only, saving the provisions given below in Norm 34 and in Norm 35 concerning those who are "impeded."
27. The three conditions may be fulfilled several days before or after the performance of the prescribed work*(see Note Below); it is, however, fitting that Communion be received and the prayer for the intention of the Sovereign Pontiff be said on the same day the work is performed.
28. A single sacramental confession suffices for gaining several plenary indulgences; but Communion must be received and prayer for the intention of the Sovereign Pontiff must be recited for the gaining of each plenary indulgence.
29. The condition of praying for the intention of the Sovereign Pontiff is fully satisfied by reciting one Our Father and one Hail Mary; nevertheless, each one is free to recite any other prayer according to his piety and devotion.
31. An indulgence cannot be gained by a work, to which one is obliged by law or precept. unless the contrary is expressly stated in the grant; one, however, who performs a work which has been imposed as a sacramental penance and which happens to be one enriched with an indulgence, can at the same time both satisfy the penance and gain the indulgence.
32. An indulgence attached to a prayer can be acquired by reciting the prayer in any language, provided the fidelity of the translation is vouched for by a declaration either of the Sacred Penitentiary or of any Ordinary or Hierarch of those places, where the language of the translation is the one commonly spoken.
33. To gain an indulgence attached to a prayer, it is sufficient to recite the prayer alternately with a companion or to follow it mentally while it is being recited by another.
NOTE ON TIME OF PERFORMANCE
On January 29, 2000, Cardinal William Wakefield Baum, the Major Penitentiary of the Vatican's Apostolic Penitentiary, modified the time frame for gaining the conditions on gaining a Plenary Indulgence to 20 days:
It is appropriate, but not necessary, that the sacramental Confession and especially Holy Communion and the prayer for the Pope's intentions take place on the same day that the indulgenced work is performed; but it is sufficient that these sacred rites and prayers be carried out within several days (about 20) before or after the indulgenced act. Prayer for the Pope's intentions is left to the choice of the faithful, but an "Our Father" and a "Hail Mary" are suggested. One sacramental Confession suffices for several plenary indulgences, but a separate Holy Communion and a separate prayer for the Holy Father's intentions are required for each plenary indulgence.
On February 18, 2005, Ioannes F. Girotti, O.F.M. Conv. Regent, clarified in a letter to a representative of EWTN Television
that 20 days was not only for the Jubilee Year of 2000 but from that time onwards/indefinitely. (Prot. N. 39/05/I of the Apostolic Penitentiary).
This is a major relaxation of previous requirements, particularly for confession, which had been previously interpreted as eight days.