Does English have a future tense? Many linguists say no.
'English has no future tense, because it has no future tense inflections'
by Richard Nordquist
Updated April 30, 2017
Legend has it that the final words of French grammarian Dominique Bouhours were, "Je vais ou je vas mourir; l'un et l'autre se dit, ou se disent." In English that would be, "I am about to--or I am going to--die. Either expression is used."
As it happens, there are also multiple ways of expressing future time in English. Here are six of the most common methods.
the simple present: We leave tonight for Atlanta.
the present progressive: We're leaving the kids with Louise.
the modal verb will (or shall) with the base form of a verb: I'll leave you some money.
the modal verb will (or shall) with the progressive: I'll be leaving you a check.
a form of be with the infinitive: Our flight is to leave at 10:00 p.m.
a semi-auxiliary such as to be going to or to be about to with the base form of a verb: We are going to leave your father a note. But time is not quite the same as grammatical tense, and with that thought in mind many contemporary linguists insist that, properly speaking, the English language has no future tense.
What is the difference between being able to talk about the future, and having a future tense?
PS I highly recommend checking out the comment thread that starts with chirelchirel's comment below. It offers some interesting twists and turns on this topic.
I'm not sure what to make of this as Finnish doesn't have a future tense, we use the present tense to express future and we also have some structures with auxiliary verbs. But then we also have compound tenses (perfect and pluperfect) for the past that are formed with past tenses of olla (to be) that are conjugated and a partciple of the main verb... so I don't really see a problem in labeling will+verb as a future tense at the same time as I understand perfectly how it can be possible to express future without a specific tense.
It probably merits mentioning that in linguistic logic, present perfect and pluperfect aren't "tenses." They're aspects of the present and past tenses (the perfect aspect in particular).
I don't think the issue is properly about auxiliary verbs. For instance, I don't think the statement that English has only two tenses means that one is also stating that Russian doesn't have a future tense for imperfective verbs just because they happen to require an auxiliary verb (i.e. it's the specific nature of the auxiliary verbs, not their mere existence that matters), but I might easily be wrong.
The idea that English wouldn't have a future tense becomes increasingly sillier when you start comparing it languages that actually lack that form. I say this, coming from a language that officially (I kinda also wanna say traditionally) does not have a future tense, but in which some colloquial forms are starting to create one.