Duration
An effect’s duration tells you how long the effect lasts. If a spell, ability, or item has a specific duration and creates one or more effects, those effects last for the duration unless the specific effect notes otherwise.
Sometimes an effect is suppressed without being negated or dispelled. When this happens, the effect’s duration is unchanged. It still ends at the same time it would have ended if it had not been suppressed.
Source
Core Rulebook pg. 270
Durations are usually measured in rounds, minutes, hours, days, or other increments. When the time of the effect’s duration is up, the energy or force empowering the effect goes away and the effect ends. If an effect’s duration is variable, the duration is rolled secretly by the GM so you don’t know how long the effect will last. Whenever an effect’s duration is expressed in a standard unit that measures time, such as hours, days, or even years, it refers to those units as expressed in Pact Standard Time. Under this scheme, a day has 24 hours of 60 minutes each, and a year has 365 days (or 52 weeks). For more information about time and similar concepts in Starfinder, see Time on page 430. Source Core Rulebook pg. 270 |
The effect comes and goes the instant it is created, though its consequences might last longer. Source Core Rulebook pg. 271 |
The effect remains until is undone through some method, such as by dispel magic for permanent spells. Source Core Rulebook pg. 271 |
When an effect has a duration of concentration, the effect lasts as long as you concentrate on it. Concentrating to maintain an effect is a standard action. Any factor that could break your concentration while you are performing activities that require focus (such as casting a spell) can also break your concentration while you’re maintaining an effect, causing the effect to end. See Concentration and Interrupted Spells on page 331 for more details. You can neither use an effect that requires concentration nor cast a spell while concentrating on an effect. Some effects last for a short time after you cease concentrating—typically 1 round per level, though individual effects may vary as noted in their descriptions. Source Core Rulebook pg. 271 |
Occasionally an effect lasts for a set duration, or until it is triggered or discharged. Source Core Rulebook pg. 271 |
Some effects, most notably spells, have a range of touch (see Range below) and require an action to activate. In most cases, if you don’t discharge a touch effect on the round you create it, you can postpone the discharge of the effect (also known as holding the charge) indefinitely. You can make touch attacks round after round until the effect is discharged. If you make any other attack, activate another ability, or cast a spell during this time, the touch effect dissipates. Some touch spells allow you to touch multiple targets as part of the spell. You can’t hold the charge of such a spell; you must touch all targets of the spell in the same round that you finish casting the spell. Source Core Rulebook pg. 271 |
If the duration of a spell or effect ends with “(D),” you can dismiss the effect at will as a standard action. You must be within range of the effect and be able to fulfill the same conditions required to create the effect—such as being able to concentrate to cast a spell or having access to the equipment that created the effect— though you do not actually need to spend the appropriate action. An effect that depends on concentration is dismissible by its very nature, and dismissing it does not take an action, since all you have to do to end the effect is to stop concentrating on your turn. Source Core Rulebook pg. 271 |