Snapshot (what most people want to know first)

Homicide (Art. 249, Revised Penal Code) → reclusión temporal Range: 12 years & 1 day to 20 years (divisible into 3 periods; see below). Usually served as an indeterminate sentence (a minimum within prisión mayor and a maximum within reclusión temporal) when the Indeterminate Sentence Law applies.
Murder (Art. 248, RPC) → reclusión perpetua (formerly “reclusión perpetua to death”; death penalty abolished by R.A. 9346) Effect: Reclusión perpetua is indivisible, legally served for 20 years & 1 day up to 40 years for purposes of service and accessory penalties. No parole if the sentence is reclusión perpetua (R.A. 9346). Ordinary mitigating or aggravating circumstances do not change this single penalty (Art. 63), unless a privileged mitigating reduces the penalty by degree.

The Doctrinal Basics

1) What distinguishes homicide from murder?

Homicide is the unlawful killing of a person without any qualifying circumstance.
Murder is homicide qualified by at least one of the statutory circumstances (e.g., treachery/alevosía, evident premeditation, cruelty, price/reward/promise, by means of fire, explosion, poison, on occasion of calamity, with abuse of superior strength, by means of motor vehicles, etc.). Presence of any qualifying circumstance elevates the felony to murder and fixes the penalty at reclusión perpetua (since death is no longer imposable).

2) Penalty structures and periods

Reclusión temporal (for homicide) is divisible and split into periods:
- Minimum: 12 years & 1 day → 14 years, 8 months
- Medium: 14 years, 8 months & 1 day → 17 years, 4 months
- Maximum: 17 years, 4 months & 1 day → 20 years
Reclusión perpetua (for murder) is indivisible. Art. 63 governs: the court imposes it as is regardless of ordinary mitigating or aggravating circumstances (those affect accessory penalties and civil liability, but not the indivisible principal penalty).

3) Indeterminate Sentence Law (ISL)

Applies to homicide (reclusión temporal): court imposes a minimum within the next lower penalty (prisión mayor, i.e., 6 years & 1 day → 12 years) and a maximum within reclusión temporal, adjusted by Art. 64 (considering mitigating/aggravating).
Does not apply when the penalty imposed is reclusión perpetua (murder). Hence no parole under R.A. 9346 for those actually sentenced to reclusión perpetua.

How mitigating/aggravating circumstances affect the years

Homicide (divisible penalty; Art. 64 rules)

With neither mitigating nor aggravating: impose medium period of reclusión temporal.
With one or more mitigating, and no aggravating: minimum period.
With one or more aggravating, and no mitigating: maximum period.
Offsetting: mitigating and aggravating offset each other.

Result: Real-world homicide sentences often look like: “8 years of prisión mayor as minimum, to 14 years & 8 months of reclusión temporal as maximum,” or “10 years, 8 months & 1 day of prisión mayor as minimum, to 17 years, 4 months of reclusión temporal as maximum,” depending on the Art. 64 calculus.

Murder (indivisible penalty)

Ordinary mitigating or aggravating do not change reclusión perpetua (Art. 63).
Privileged mitigating (e.g., minority under R.A. 9344; incomplete self-defense under Art. 69) can reduce the penalty by degree:
- Murder (reclusión perpetua) ↓ one degree → reclusión temporal (then ISL applies).
- If two privileged mitigatings exist, another degree lower → prisión mayor (rare).

Attempted & Frustrated stages (very practical in charging and plea-bargaining)

By statute, the penalty for attempted and frustrated felonies is lowered by degree(s):

Felony	Consummated	Frustrated	Attempted
Homicide	Reclusión temporal	Prisión mayor (1 degree lower)	Prisión correccional (2 degrees lower)
Murder	Reclusión perpetua	Reclusión temporal (1 degree lower)	Prisión mayor (2 degrees lower)

Once you’re within a divisible penalty at these stages, ISL & Art. 64 period rules apply.

Accessory penalties & collateral consequences

Reclusión temporal carries civil interdiction during sentence and perpetual absolute disqualification (during the maximum period), among others.
Reclusión perpetua carries perpetual absolute disqualification and civil interdiction for life; no parole (R.A. 9346).
Preventive imprisonment credits (Art. 29, as amended) typically apply if the accused was detained before judgment (subject to exclusions).

Parole, probation, and GCTA—quick cues

Probation is not available if the accused is sentenced to more than 6 years of imprisonment; homicide sentences almost always exceed this.
Parole is possible for homicide (since ISL applies and the maximum is divisible), subject to Parole Board discretion.
Parole is barred for reclusión perpetua (murder).
GCTA (Good Conduct Time Allowance) may reduce service time subject to statutory/regulatory exclusions and actual jail practice; it does not alter the judicially imposed penalty.

Civil liability (separate from imprisonment)

Conviction for homicide or murder entails civil liability (death indemnity, moral/exemplary damages, loss of earning capacity, funeral expenses). Updated amounts are jurisprudential and periodically adjusted. A full acquittal on reasonable doubt may still carry civil liability if the act is proven but authorship/culpability is uncertain—depending on the judgment’s tenor.

Typical sentencing patterns (illustrative, not exhaustive)

Homicide with 1 ordinary mitigating (e.g., voluntary surrender) and no aggravating:
- Choose minimum period of reclusión temporal for the maximum term; pick a minimum term within prisión mayor.
- Example: 8 years & 1 day of prisión mayor (min) to 14 years, 8 months of reclusión temporal (max).
Murder with one mitigating (e.g., intoxication not habitual) and no aggravating:
- Still reclusión perpetua (indivisible).
- No parole; accessory penalties attach.
Murder by a 17-year-old (minority):
- Privileged mitigating reduces penalty by degree → reclusión temporal (then apply ISL and Art. 64). Child in Conflict with the Law rules (R.A. 9344) on suspension of sentence/diversion may govern depending on age and circumstances.

Practical charging & defense notes

Qualifying circumstances must be specifically alleged and proven to convict for murder. If the qualifying fails, the court generally convicts for homicide.
Complex/compound crimes (e.g., homicide with physical injuries on multiple victims) follow separate rules on complexing or separate informations; this can affect the penalty and civil awards.
Plea-bargaining often uses the attempted/frustrated ladder to bring a sentence into prisión mayor/correccional ranges (with probation sometimes in play only if the imposed penalty does not exceed 6 years).

Key Takeaways

Homicide → 12y1d–20y (reclusión temporal); ISL applies, parole may be possible.
Murder → reclusión perpetua (post–R.A. 9346), no parole; ordinary mitigating/aggravating don’t change the indivisible penalty (Art. 63).
Privileged mitigating circumstances can reduce by degree, potentially moving murder down to reclusión temporal (then ISL math applies).
Attempted/frustrated stages lower the penalty by one or two degrees.
Civil liability is separate and typically substantial; imprisonment ranges are distinct from civil indemnities.

If you want, I can convert this into a sentencing calculator (with sliders for mitigating/aggravating and crime stage) so you can see the exact indeterminate sentence range that would likely be imposed in your scenario.