What we researched for this specific generation: where an enclosure actually fits, what the factory speakers are, how the factory audio is wired, and which real builds and commercial products exist for it. Confidence badges say how well each figure is sourced — this is research, not manufacturer spec.
Body styles covered: 5-Door Liftback/Hatchback
These are researched envelopes, not a guarantee. Measure your own vehicle — the numbers here tell you what to expect, not what you have.
| Location | behind rear seat, spare tire well, or rear deck |
|---|---|
| Outer bounding box | No independently measured raw cavity envelope found. |
| Known obstructions | AWD-e trims (introduced late 2018 for the 2019 model year): a rear electric motor drives the rear wheels with no mechanical driveshaft, the same general e-Four/AWD-e pattern confirmed safe on other Toyota pages — not independently verified as cargo-neutral specifically for THIS vehicle, so do not assume it is. Toyota figures show AWD-e is NOT cargo-neutral: the 2018 Prius release says "Up to 65.5 cubic feet of cargo space" (seats folded; 2018 had no AWD-e, so this is the FWD car); the 2019 AWD-e release says "62.7 cu. ft. of carrying space with the standard 60:40 split rear seatbacks lowered" — 2.8 cu ft less, and AWD-e uses a Ni-MH battery. Toyota gives no behind-the-seat figure for either. The FWD lithium-ion battery is under the rear seat, not under the luggage area (2016 release). |
Suggested configurations for this vehicle, not prescriptions. Run the numbers in the Box Builder before you buy anything.
| Subwoofers | 1x8" powered, behind the rear seat (preserves trunk) |
|---|---|
| Box type | n/a — powered unit |
| Location | behind rear seat |
| Subwoofers | 1x8" or 1x10" sealed, rear-deck infinite-baffle integration |
|---|---|
| Box type | infinite baffle (uses trunk air volume, not a discrete sealed box) |
| Location | rear deck |
Sizes and depths below are what research turned up for this generation. Confirm against your own vehicle before cutting or ordering — trim levels vary.
| Factory speaker size | not independently confirmed by exact size — forum sourcing confirms there IS enough room in the front door for a speaker with a heavier magnet than stock, and that the factory input signal there is full-range (not high-pass filtered). Likely-similar reference: the sister 2nd/3rd Gen Prius pages confirm a 6.5"/6.75" door midbass convention, but this was not independently re-confirmed for this specific 4th Gen. |
|---|---|
| Known obstructions | None specifically documented |
| Adapter bracket needed | unconfirmed |
| Tweeter | Not independently confirmed for this generation — likely dash-corner and/or door-mounted per the general Toyota JBL pattern, not pinned down specifically. |
| Factory speaker size | not independently confirmed by exact size |
|---|---|
| Known obstructions | None specifically documented |
| Adapter bracket needed | unconfirmed |
| Factory amp / premium audio | JBL-branded systems existed on this generation, but sourcing confirms neither the standard nor JBL system includes a true factory subwoofer — consistent with the same confirmed absence noted on the 2nd Gen page. Toyota pressroom: the 2016 and 2017 releases say the Prius Four "exclusively offers the Entune Premium JBL Audio system" with "10 JBL GreenEdge speakers in eight locations"; the 2018 release says "10 JBL GreenEdge Speakers in six locations" (Toyota's own pages differ on locations). Other grades: six speakers. 2019: "Limited grade comes standard with the Entune Premium JBL Audio". Toyota does not say whether any of the 10 is a subwoofer, so the "no true factory subwoofer" finding stays forum-sourced. |
|---|---|
| Adding subs without a head-unit swap | Confirmed via detailed forum/how-to guidance, with a genuinely important HYBRID-SPECIFIC ELECTRICAL CAUTION: avoid 1-ohm final-impedance amplifier loads specifically on this hybrid platform — a 1-ohm load stresses the hybrid alternator and can trigger real dashboard error codes, a more specific and consequential warning than the general '30A max' guidance already standing on other vehicles covered here for hybrids. Specific power-wire routing path confirmed: through the firewall above the gas pedal, via a spare nipple already present in the factory grommet — a genuinely convenient, no-drilling route. |
| Head unit | No replacement needed |
Three distinct, named installation philosophies confirmed for this generation: (1) behind the rear seat, which preserves the trunk itself; (2) in the spare tire well, hidden but trading away spare-tire use; (3) integrated into the rear deck as an infinite-baffle design, using the trunk's own air volume rather than a discrete sealed box. General sourcing mentions NVX and similar brands offer pre-loaded enclosures 'shaped to fit specific Prius generations,' but no product explicitly named for THIS generation (2016-2022) specifically was confirmed. EPA luggage figure (fueleconomy.gov, hatchback, the base Prius record): 27 cu ft for 2016, 2019 and 2022. On a hatchback or wagon EPA's number is an index computed from SAE J1100 dimensions (40 CFR 600.315-08), not the seats-up cargo volume, and never a box volume.
AWD-e (introduced 2019 model year): a rear electric motor drives the rear wheels directly with no mechanical driveshaft or transfer case — the same general e-Four-family design already confirmed safe/cargo-neutral on other Toyota AWD-e systems elsewhere in this catalogue, though not independently re-verified specifically for the Prius AWD-e's own cargo impact. Standard (FWD) hybrid: no unusual battery placement concerns beyond the general hybrid-alternator 1-ohm-load caution in audio integration.
Outside links. Some are commercial products, some are owner builds posted on forums — the label says which. We do not endorse any of them.
Each link opens the tool with this vehicle already selected.
Measure your own vehicle. Trim levels, factory subwoofer options, and mid-generation changes all move these numbers, and a box cut to a researched figure that does not match your truck is wasted wood. Where a badge reads Unconfirmed, treat the value as a starting point for your own measurement, not as an answer.