The future tense is roughly equivalent to English will ... (or 'll ...). As with English will, the Spanish future tense can be used not only to express a future event or state, but also for other "modal" uses such as expressing or implying a supposition, prediction, approximation or command. It is often argued that in spoken Spanish at least, these "modal" uses represent the most common use of the future tense and that simple 'futurity' is instead expressed by other means, such as ir a plus infinitive1.
The vast majority of verbs form the future tense by adding the future tense endings, which are the same for all verbs, to the infinitive. The future tense endings are similar to the present tense of haber (and historically this is how the future tense is derived):
The word stress is always "anchored" on the first syllable of the future tense ending, as reflected by the written accent on the one-syllable endings.
Irregular future tense forms
A handful of verbs add the above future tense endings to a modified version of the infinitive. Some common irregular future tenses include: