A form you should recognize, not imitate freely
Modern Spanish learners spend a lot of time on the present subjunctive, imperfect subjunctive, and pluperfect subjunctive. Then one day they encounter a strange form:
fuere
hubiere
tuviere
procediere
It looks like a future. It behaves like a subjunctive. It appears in legal clauses, older literature, proverbs, and formulaic expressions.
This is the future subjunctive.
The key principle is:
The future subjunctive is mostly obsolete in everyday modern Spanish, but it survives in legal, archaic, proverbial, and formulaic contexts. Learners should recognize it without trying to use it as normal speech.
What the future subjunctive used to do
Historically, the future subjunctive was used in subordinate clauses referring to uncertain future events, especially after words like si, cuando, quien, and donde.
Older or formal-style examples resemble:
Si alguien incumpliere la norma...
If someone should violate the rule...
Quien lo hiciere...
Whoever should do it...
In contemporary everyday Spanish, these are normally replaced by the present subjunctive or indicative depending on structure:
Si alguien incumple la norma...
If someone violates the rule...
Quien lo haga...
Whoever does it...
How to recognize the forms
Regular future subjunctive endings resemble:
hablare
hablares
hablare
habláremos
hablareis
hablaren
For comer:
comiere
comieres
comiere
comiéremos
comiereis
comieren
For vivir:
viviere
vivieres
viviere
viviéremos
viviereis
vivieren
Irregular stems often resemble preterite-derived stems:
ser/ir → fuere
haber → hubiere
tener → tuviere
estar → estuviere
hacer → hiciere
The compound form uses hubiere + participle:
hubiere terminado
shall have finished / has finished, in archaic-legal framing
Legal Spanish preserves it
Legal and administrative Spanish may preserve future subjunctive forms because legal language values formula, continuity, and precision.
Examples:
Si procediere...
If appropriate / if it should proceed.
Cuando hubiere lugar...
When there is cause / when appropriate.
El que incumpliere...
Whoever violates / should violate.
A learner reading contracts, statutes, regulations, or older legal templates should not panic. The practical translation is often a modern present or future condition.
Fixed expressions and literary flavor
Some forms survive in fixed expressions:
Sea lo que fuere.
Whatever it may be.
Venga de donde viniere.
Wherever it may come from.
Quienquiera que fuere.
Whoever it may be.
These expressions sound formal, literary, archaic, or elevated depending on context. Everyday Spanish would often say:
Sea lo que sea.
Whatever it is.
Venga de donde venga.
Wherever it comes from.
Quienquiera que sea.
Whoever it is.
The older form can give a text a solemn, legal, poetic, or old-fashioned tone.
Do not confuse fuere with fuera
Learners may confuse:
fuera
imperfect subjunctive of ser/ir
fuere
future subjunctive of ser/ir
Compare:
Si fuera posible, lo haría.
If it were possible, I would do it.
Si fuere necesario...
If it should be necessary...
archaic/legal style
In modern speech, fuera is common. Fuere is not.
Modern replacement: present subjunctive or indicative
Contemporary Spanish usually replaces future subjunctive with present subjunctive in many subordinate clauses:
Quienquiera que sea.
Whoever it is.
Cuando llegue.
When he arrives.
Sea lo que sea.
Whatever it is.
In si clauses, modern Spanish usually uses the indicative for open conditions:
Si procede, se aplicará la norma.
If appropriate, the rule will apply.
Not:
Si procediere...
unless the register is legal or archaizing.
Why recognition matters
Even if you never produce the future subjunctive, you should recognize it because it appears in:
- legal language;
- older literature;
- formal proclamations;
- archaic formulas;
- proverbs;
- ceremonial or deliberately elevated style.
A learner who recognizes the form can read the sentence calmly. A learner who does not may mistake it for future indicative, conditional, or a typo.
Future subjunctive is not the future indicative
Many forms look deceptively close:
hablaré
I will speak
hablare
if/when/whoever should speak, archaic/legal subjunctive
The accent mark is not decoration. Hablaré is future indicative. Hablare is future subjunctive. In speech, the difference can be subtle or lost depending on context, but in writing it matters.
Compare:
El testigo hablará mañana.
The witness will speak tomorrow.
Quien hablare sin autorización...
Whoever should speak without authorization...
The second belongs to legal or archaizing style. A modern neutral version would be:
Quien hable sin autorización...
Modernize by function, not word-for-word form
When reading legal or old-fashioned future subjunctive, do not try to preserve an English “shall” every time. First identify the function.
Si procediere la sanción, se notificará al interesado.
If the sanction is appropriate, the interested party will be notified.
Cuando hubiere terminado el plazo...
When the deadline has ended...
El que incumpliere esta obligación...
Whoever violates this obligation...
In modern plain Spanish, these often become:
Si procede...
Cuando haya terminado...
El que incumpla...
The future subjunctive is therefore a recognition problem and a register problem. It tells you the text is using an older or formulaic legal architecture. It does not require you to imitate that architecture in ordinary writing.
Example bank walkthrough
fuere
Future subjunctive of ser/ir.
Learner action: recognize as archaic/legal; modern equivalent often sea or fuera depending on context.
hubiere
Future subjunctive of haber.
Learner action: recognize in compound forms like hubiere cumplido.
tuviere
Future subjunctive of tener.
Learner action: read as “should have” or modern tenga/tiene depending on structure.
quienquiera que fuere
Formulaic “whoever it may be.”
Learner action: compare with quienquiera que sea.
si procediere
Legal “if appropriate / if it should proceed.”
Learner action: do not imitate in normal conversation.
sea lo que fuere
Fixed expression meaning “whatever it may be.”
Learner action: recognize literary or formal tone.
Recognition routine
When you see a suspicious form ending in -re, ask:
- Is the text legal, formal, old, or literary?
- Does the clause begin with si, cuando, quien, donde, or a similar connector?
- Does the form look like fuere, hubiere, tuviere, hiciere, procediere?
- Would modern Spanish use present subjunctive or indicative here?
- Is the expression fixed?
If yes, you are probably looking at the future subjunctive.
Suggested interactive module: archaism detector
A strong tool for this article would flag future subjunctive forms and translate them into modern equivalents.
Suggested functions:
- Form detector: fuere, hubiere, tuviere, procediere.
- Register label: legal, literary, proverbial, archaic.
- Modern equivalent: sea, tenga, procede, haya.
- Clause parser: si, quien, cuando, donde.
- Compound mode: hubiere + participle.
- Production warning: recognition target, not everyday usage.
- Text examples: legal clause, proverb, literary sentence.
Final rule
The future subjunctive is a living fossil.
You do not need to use it in ordinary Spanish, but you should recognize it in law, literature, formulas, and archaic style. When you see fuere, hubiere, or tuviere, translate the function, not the strangeness.
Modern Spanish mostly moved on. Documents did not always follow.