How long does a touch spell last before my familiar can deliver it?

Question

The Pathfinder SRD says about Familiar Abilities:

Deliver Touch Spells (Su): If the master is 3rd level or higher, a familiar can deliver touch spells for him. If the master and the familiar are in contact at the time the master casts a touch spell, he can designate his familiar as the “toucher.” The familiar can then deliver the touch spell just as the master would. As usual, if the master casts another spell before the touch is delivered, the touch spell dissipates.

How long does a spell cast this way last? Is it like a stored bullet, since it says the spell dissipates if I cast another one? E.g., could I cast a touch spell for my familiar before combat, then during combat have it cast the spell, then I myself cast another spell?

Answer 1

Your familiar is now “holding the charge” for the touch spell. This is an ordinary option for the caster of a touch-range spell, just transfered to the familiar. The rules for it are here:

Touch Spells and Holding the Charge: In most cases, if you don't discharge a touch spell on the round you cast it, you can hold the charge (postpone the discharge of the spell) indefinitely. You can make touch attacks round after round until the spell is discharged. If you cast another spell, the touch spell 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.

Specifically, it says “you [in this case, your familiar] can make touch attacks round after round until the spell is discharged.” So that is what your familiar does.

Also, I recommend looking at the related links to the right; a number of questions about touch spells and holding the charge have come up here.