The duration of an enchantment determines how long the enchantment lasts.
The minimum value that can be given to the Duration of an enchantment is zero.
The magician casting an enchantment should define the enchantment's effects as being either:
The amount added to the difficulty of the enchantment depends on the Duration level chosen and whether the enchantment's effects are lasting or reducing over the duration:
| Duration level | Lasting over duration | Reducing over duration |
| Instantaneous (i.e. no lasting effect) | 0 | 0 |
| 1 Combat Turn (i.e. 5 seconds) | 1 | 1 |
| 1 Minute | 2 | 1 1/2 |
| 1 Hour | 3 | 2 |
| 1 Day | 4 | 2 1/2 |
| 1 Week | 5 | 3 |
| 1 Month | 6 | 3 1/2 |
| 1 Year | 7 | 4 |
| 10 Years | 8 | 4 1/2 |
| 100 Years | 9 | 5 |
| Permanent | 10 | 6 |
Normally, an enchantment with a duration requires the caster to continue to devote some concentration to continuing the magical effect. This means that the enchantment will cease if the caster of the enchantment is distracted from it (e.g. by being stunned or falling unconscious). In addition, the act of concentrating on the enchantment means that the caster has a penalty of -1 on all dice rolls per enchantment that they are maintaining.
To avoid this penalty, a caster can instead make the enchantment autonomous so that he/she does not have to concentrate on maintaining it. The difficulty associated with the duration of the enchantment is increased by +3 if the enchantment is autonomous and will keep going even if the caster is unconscious or dead. Any enchantment that is focused in an item must be made autonomous. In addition, since otherwise enchantments will fail when the caster falls asleep, it is normal for most enchantments with a duration of >1 day to also be autonomous.
Finally, the difficulty associated with the duration of the enchantment is reduced by -2 if the enchantment is so intense that all the caster can do while the enchantment lasts is to concentrate on maintaining the enchantment, i.e. the enchantment ceases if he/she tries anything else. Since the minimum duration value that can be given to an enchantment is zero, the benefit is only -1 difficulty if the duration is 1 combat turn (and no benefit if the duration is instantaneous).
If a character benefits from a long-term enchantment (>1 day, autonomous) either because he/she is the target of the enchantment or because the enchantment was focused into an item which he/she carries, the referee will normally rule that the character must take the Enchanted talent and pay character points to reflect the benefit of the long-term enchantment on the character. Similarly, if a character suffers ill effects from a long-term enchantment, the referee will normally award the character a Cursed disability to compensate for the ill effects. A focused enchantment on an item tends to cost fewer cps but also has a wealth cost, whereas a long-term enchantment on the character directly has no wealth cost but tends to cost more cps as a talent.