2026 BMW 4 Series Convertible

Volume 430i Convertible uses BMW's 2.0L B48 TwinPower Turbo inline-4 with 48V mild hybrid producing 255 hp; M440i xDrive steps up to 382 hp with the B58 3.0L inline-6, and the range tops at 523 hp in the M4 Competition xDrive Convertible (S58 twin-turbo I6).

430i Convertible peaks at 295 lb-ft; M440i xDrive at 369 lb-ft, and the M4 Competition xDrive Convertible at 479 lb-ft — same torque figures as the corresponding Coupe variants.

BMW quotes 5.8 s for the volume 430i xDrive Convertible — slightly slower than the equivalent Coupe due to the softtop's added weight; M440i xDrive Convertible runs 4.4 s, and the M4 Competition xDrive Convertible is claimed at 3.6 s.

The B48 2.0T in the 430i is smooth and linear with the 48V mild hybrid smoothing stop-start and low-rpm response; the B58 inline-six in M440i is a benchmark for refinement, and the S58 in the M4 Competition delivers ferocious yet well-metered power with only mild turbo character.

All 4 Series Convertible variants use the ZF 8-speed Sport Automatic, widely regarded as the best conventional automatic on sale — crisp, quick, decisive shifts with well-tuned Sport logic; unlike the Coupe there is no manual option in the Convertible (M4 Convertible is Competition xDrive automatic only).

xDrive AWD is optional on the 430i, standard on the M440i, and the M4 Convertible is offered only as the M4 Competition xDrive — with a rear-biased tune and 2WD mode — so xDrive is broadly available across the lineup; system is a competent on-road setup without low range or terrain modes.

Convertible is gas-only with no hybrid, PHEV, or EV variant, and its lineup is narrower than the Coupe's — three distinct engines (255 hp 2.0T I4 mild hybrid, 382 hp 3.0T I6 mild hybrid, 523 hp twin-turbo I6) but no base M4 manual and no M4 CS variant, so buyers get the tune spread without the halo track model.

EPA combined figure for the 2026 430i xDrive Convertible with the B48 2.0L turbo I4 and 48V mild-hybrid assist. The soft-top convertible loses roughly 3 MPG combined vs. the 4 Series Coupe (30 MPG) because of the ~275 lb weight penalty from body reinforcement and the retractable soft-top mechanism.

EPA city rating for the 430i xDrive Convertible with 48V MHEV auto-stop assist — about 2 MPG below the equivalent Coupe due to the extra convertible body mass.

EPA highway rating for the 430i xDrive Convertible. RWD 430i is 1-2 MPG better on the highway thanks to lower driveline losses.

Computed from BMW's ~15.6-gallon fuel tank and EPA combined 27 MPG for the 430i xDrive Convertible. Real-world range varies with top-down driving, fuel grade, and drive mode.

EPA-style annual fuel cost for the 2026 430i xDrive Convertible at 15,000 mi/yr, 55/45 city/highway split, using premium gasoline pricing. Runs $150-200/yr higher than the 4 Series Coupe due to the lower combined MPG.

Both the 430i and M440i Convertible require premium unleaded (91 octane or higher) per BMW's owner's manual and window sticker — no regular-fuel option and no home-charging alternative anywhere in the Convertible lineup.

NHTSA does not publish a comprehensive rating for the 4 Series Convertible body style; convertibles generally do not receive full test batteries. Estimate carries over from the shared CLAR platform (3 Series 5-star overall) with a slight discount for the removable roof.

IIHS does not perform its full crashworthiness battery on convertibles (no roof-strength test), so the 4 Series Convertible is not eligible for a Top Safety Pick award. Structural side-impact and small-overlap performance is expected to be broadly comparable to the coupe (Good moderate overlap front, Acceptable updated side) but cannot be independently verified.

BMW Active Driving Assistant is standard on all 4 Series Convertible trims (forward collision warning with city collision mitigation/AEB, blind-spot detection, lane departure warning, rear cross-traffic alert, park distance control). Full-speed adaptive cruise with stop-and-go and lane centering remain a paid Driving Assistance Professional Package upgrade — behind Mercedes CLE Convertible's more inclusive standard ADAS bundle.

BMW's front collision prevention has earned Superior daytime and Advanced/Superior nighttime pedestrian ratings on the shared 3 Series platform; the 4 Series Convertible uses the same camera + radar sensor suite, though not separately IIHS-rated.

Blind-spot detection and rear cross-traffic alert are standard across the 4 Series Convertible lineup as part of Active Driving Assistant. Intervention is alert-only on the volume 430i, but the system is especially valuable here because the fabric roof creates a large rear-quarter blind zone with the top up.

Lane departure warning is standard; active lane keeping and lane centering come with the Driving Assistance Professional Package. When equipped, BMW's centering is smooth and confidence-inspiring per reviewer testing on shared 3/4 Series hardware.

Optional Driving Assistance Professional adds full-speed-range adaptive cruise with stop-and-go and an integrated highway assist; BMW's calibration (smooth braking, quick resume, natural gap keeping) is among the best in class. Points off because the full system is not standard on the volume trim.

BMW Highway Assistant enables hands-free driving up to 85 mph on divided US highways with driver eye monitoring, as part of the Driving Assistance Professional Package. Mapped-road coverage is narrower than GM Super Cruise's ~750k-mile network but the system is mature and available on the 4 Series Convertible.

Standard LED headlights with automatic high beam; adaptive LED optional on upper trims. IIHS testing on the current 4 Series has generally shown Acceptable rather than Good on volume-trim headlights; adaptive units improve results but are trim-locked.

Top-down visibility is essentially unrestricted, but with the fabric roof raised the rear three-quarter view is heavily blocked and the rear window is small — a bigger blind zone than the coupe. Standard reversing camera and available 360-degree Parking Assistant Plus help, but reviewers consistently flag rear/rear-quarter visibility with the top up as a weak point.

Two-door 2+2 configuration forces child-seat installation through a single narrow doorway after tumbling the front seat; the convertible top mechanism further limits vertical clearance and rear-seat width is limited. LATCH anchors are recessed under upholstery. Not a practical family carrier.

Two-door 2+2 layout with two front bucket seats and a rear bench sculpted for two, per BMW spec sheet; unchanged for 2026.

Soft-top design gives noticeably more front headroom than the Coupe's 38.0 in; unchanged G23 dimension carried into 2026.

Front legroom mid-band for the convertible segment; carries over unchanged from the G23 platform for 2026.

With the soft top up, rear headroom is meaningfully better than the coupe's 35.2 in though still tight for tall adults; unchanged for 2026.

Rear legroom is tight — usable for children or short adult trips only; the convertible loses ground versus the coupe's already-cramped 34.5 in due to top-mechanism intrusion.

Soft-top mechanism consumes trunk volume — the 4 Series Convertible's 9.0 cu ft (top up) trails the coupe's 12.0 cu ft substantially, and shrinks to 7.8 cu ft with the roof stowed.

Typical BMW center console, cupholders, door pockets, and modest glovebox — competent but not standout. The soft-top mechanism eliminates the coupe's ski pass-through and eats into behind-seat cargo, and the top-down trunk shrinks meaningfully. Adequate for a convertible but nothing innovative.

Same excellent front sport seats as the coupe — firm, well-bolstered, multi-way power with adjustable side bolsters and thigh extension; broadly praised for long-haul comfort. Rear seats are cramped (see legroom) but shaped well for the two they carry.

Adaptive M suspension (standard on M440i, optional on 430i) delivers a supple Comfort-mode ride with strong body control. The convertible is roughly 350 lbs heavier than the coupe and shows very modest cowl shake over sharp inputs — well controlled but not quite as composed as the fixed-roof car.

Soft-top construction inevitably admits more wind and road noise than the coupe or a folding-hardtop convertible. Top-up the cabin is reasonably hushed at moderate speeds but wind noise climbs on the highway; top-down it's obviously loud. Well insulated for a soft-top but not library-quiet.

Standard dual-zone auto climate, heated front seats, and available heated steering wheel; the convertible-specific Air Collar neck warmer (optional) and heated armrests are genuine top-down comfort features. Ventilated seats and Comfort Access with remote pre-conditioning round out a rich package.

Base 430i Convertible commands a ~$7,000 body-style premium over the 430i Coupe due to the retractable soft-top mechanism, structural reinforcement, and unique interior trim. Sits above the convertible normalization band's high end.

The volume build is the 430i xDrive Convertible (~$60,900 all-in) fitted with the Premium Package (heated seats, keyless entry, wireless CarPlay/Android Auto) and the M Sport package or Convenience Package — the most-selected option groups for open-top 4 Series buyers per BMW configurator patterns.

Convertible-specific service (soft-top hydraulic pump, top-frame sensors, unique window regulators) layers ~$400–600 of expected repair exposure over the coupe's already high figure. BMW dealer labor rates, run-flat tires, and turbocharged B48 servicing push 5-year maintenance and out-of-warranty repair above the coupe/convertible segment band.

BMW convertibles depreciate faster than their coupe siblings because the used market for open-top luxury cars is thinner and heavily-optioned MSRPs don't hold. Soft-top wear concerns and seasonal-use perception soften year-4/5 residuals further than the 4 Series Coupe.

BMW's New Vehicle Limited Warranty is 4 years or 50,000 miles, whichever comes first. Standard among German luxury; matches Audi and Mercedes-Benz basic coverage.

BMW does not publish a separate extended powertrain warranty; the powertrain is covered under the same 4-yr/50k New Vehicle Limited Warranty. Well below segment leaders (Hyundai/Kia/Genesis 10-yr/100k) and matches Audi/Mercedes-Benz.

BMW Ultimate Care includes 3-yr/36,000-mi factory-scheduled maintenance (oil, filters, brake fluid, inspections) — one of the better complimentary programs in luxury (Audi and Mercedes-Benz provide little to nothing at that duration). Paired with 4-yr/unlimited-mile roadside assistance and BMW ConnectedDrive/eCall trials. No included charging/fuel credits (gas-only).

$65,975 volume-trim price minus its estimated resale value after 5 years (42% retained, or about $27,710) leaves about $38,266 in depreciation. Add the projected $9,700 in 5-year maintenance and repairs, and owning this vehicle for 5 years costs about $47,966 in total.

Shares the G22 4 Series Coupe's platform and mature B48/B58 mild-hybrid powertrains, which trend around Average in Consumer Reports predicted reliability and low-80s in J.D. Power quality. Docked a couple of points versus the Coupe for the added complexity of the G23 fabric soft-top mechanism, which introduces motors, sensors, and seals not present on the fixed-roof car.

BMW consistently lands mid-pack in dependability studies — J.D. Power 2024 VDS placed BMW near industry average and Consumer Reports 2024 brand rankings put BMW in the middle third. Not a top-5 dependability brand but well ahead of most European rivals other than Porsche.

The G23 Convertible has drawn the same modest set of G22-family campaigns (software, backup camera, seatbelt anchor, occupant classification) plus a small number of convertible-specific TSBs around soft-top operation and wind deflector fit. Nothing systemic in powertrain or fire-related actions.

The 430i's B48 2.0T and M440i's B58 3.0T inline-six (with 48V mild hybrid) are among BMW's most durable modern engines — the B58 in particular has an excellent high-mileage reputation (also used in the Toyota GR Supra) and pairs with the exceptionally proven ZF 8HP automatic.

Cabin mirrors the 4 Series Coupe — SensaTec/leatherette or Vernasca leather, aluminum or wood trims, BMW's crisp switchgear and curved display — rated as competitive-to-strong for the low-$60K luxury convertible class, though a step below the plusher Mercedes CLE Cabriolet on perceived richness.

Munich-plant assembly is consistently tight with strong panel gaps and solid door thunk, but convertibles inevitably trade some structural rigidity and NVH refinement for the folding roof — reviewers note occasional cowl shake on rougher roads and more wind noise than the Coupe. J.D. Power IQS places BMW at or slightly above industry average.

BMW operates ~340 US dealers with dense metro and suburban coverage but thinner rural presence; J.D. Power CSI rates BMW above the premium-brand average, though hourly labor rates are among the highest in the industry.

Parts availability is strong thanks to BMW's dense US network and a deep aftermarket (FCP Euro, ECS Tuning, Turner), but OEM parts and dealer labor push repair costs well above mainstream norms, and convertible-specific items — soft-top motors, cables, seals, and rear glass — add expensive failure points versus the fixed-roof Coupe.

The 2026 4 Series Convertible carries the same BMW Curved Display as the Coupe after the LCI refresh: 12.3" driver cluster merged behind one glass with a 14.9" central touchscreen, standard on the 430i volume trim. Among the largest displays in the luxury convertible segment.

iDrive 8.5 is fast and graphically rich, and the 4 Series retains the physical iDrive rotary controller alongside touch — a real usability win reviewers highlight. Minor demerits: climate migrated into the touchscreen, and open-top driving worsens screen glare and reflections vs the Coupe.

Wireless Apple CarPlay and wireless Android Auto are standard on every 4 Series Convertible trim (430i, 430i xDrive, M440i xDrive) with no subscription. Pairing is fast and stable in reviewer testing.

BMW Intelligent Personal Assistant ("Hey BMW") handles natural-language commands for climate, nav, and vehicle functions. BMW Maps with cloud-based routing and Real Time Traffic Information is standard and legitimately worth using over phone projection.

Standard 10-speaker Hi-Fi is adequate; optional Harman Kardon Surround Sound (464W, 16 speakers) via the Premium Package is the meaningful step up. No Bowers & Wilkins tier offered, and open-top acoustics fundamentally cap what any system can deliver vs the Coupe.

12.3" fully digital cluster within the Curved Display is standard on all trims. Crisp, offers multiple driving-mode layouts and integrated map view; slightly less customizable than Audi Virtual Cockpit but larger and better integrated visually.

BMW Remote Software Upgrade delivers periodic OTA updates covering iDrive, maps, and select vehicle functions. Scope is narrower than Tesla/Rivian whole-vehicle updates but broader than maps-only rivals.

My BMW app covers remote start/climate, lock/unlock, vehicle location, and BMW Digital Key Plus (Ultra Wideband) for compatible iPhone and Android devices. Core ConnectedDrive functions free for the first several years.

Two front USB-C ports and rear USB-C outlets standard; wireless phone charging tray is bundled in the Premium Package rather than standard. Adequate for the segment; no 120V outlets.

Comfort Access keyless entry with push-button start is standard on M440i and available on 430i via option group. BMW Digital Key Plus (UWB, unlocks without waking the phone) is available and rare at this price. Remote start via My BMW app included.

Rear-view camera and Park Distance Control (front and rear sensors) are standard; optional Parking Assistant Plus adds Surround View with 3D visualization and automated parallel/perpendicular parking. Image quality is good, and rear visibility with the top up makes surround view worth optioning.

Full-color HUD projecting speed, nav directions, and driver-assist status is optional via the Premium Package on 430i and included within higher option groups on M440i. Broadly attainable rather than volume-trim standard.

Two-door soft-top with LATCH at the outboard rear positions, but every child-seat load requires tipping a front seat forward, and rear legroom is even tighter than the coupe (~33 in) with severely compressed rear headroom under the folded top. Regularly frustrating for daily family logistics.

BMW's Active Driving Assistant (forward-collision warning with city AEB, blind-spot detection, lane-departure warning, active cruise) is standard, but the convertible body sacrifices some structural crash performance versus the coupe and has no current-generation IIHS Top Safety Pick or NHTSA overall rating.

Trunk shrinks to ~9.0 cu ft with the top up and ~8.0 cu ft with the top down, and rear headroom is compromised by the folded roof mechanism. Four-up plus luggage on a multi-hour trip is a serious squeeze; no rear-seat climate vents on base trims.

Same refined 2.0L turbo-four mild-hybrid, ZF 8-speed, and standard Active Driving Assistant as the coupe make it a low-fatigue commuter, and the fabric top raises quickly at up to 31 mph. Extra weight (~4,180 lb) and slightly softer structure trim the edge versus the coupe.

430i Convertible RWD returns roughly 24/33/27 mpg and xDrive ~23/31/26, a couple of mpg behind the coupe due to added weight, and premium fuel is required. BMW run-flats, brake service, and out-of-warranty costs keep per-mile expense above mainstream commuters.

Length ~187.9 in and width ~72.9 in with a ~38.7 ft turning circle mirror the coupe; standard rear camera and available Parking Assistant Plus with 360° cameras help. Over-the-shoulder visibility is worse than the coupe with the top up but excellent with the top down.

Not rated for towing in the US market, no bed, no published payload, and only a 9 cu-ft trunk (8 with the top down). Essentially no meaningful work capability.

Luxury interior with Sensatec/leather trim, carpeted trunk, and a fabric soft top that is more vulnerable to abuse than a fixed steel roof. BMW's B48 engine is durable in normal service, but the car has no fleet reputation for hard-use work.

No cargo-area 120V outlet, no bed tie-downs, no factory trailer hitch, and no roof-rack option on the convertible body. Essentially zero work-oriented provisions.

Excellent front sport seats, standard adaptive cruise and lane keep, and a 15.6-gal fuel tank yield ~420-mi highway range on premium. Top-up cabin is impressively quiet for a fabric convertible, though wind noise and the folded-top intrusion cap four-up endurance; a strong two-up tourer.

xDrive AWD is available on 430i and standard on M440i and helps with snow, but ground clearance of ~5.5 in, run-flat performance tires, and the absence of any factory roof rack (soft top) or hitch make it pavement-bound. A nice open-air scenic-drive car; not an adventure enabler.

9 cu-ft trunk (8 with the top down) with a 50/50 folding rear and a limited pass-through, no roof rails, and no factory hitch make bulky-gear hauling a real limitation — even weekend luggage for two plus golf bags is tight top-down.

Shares the CLAR platform, adaptive M suspension, and near 50/50 balance of the G22 coupe, so lateral grip and body control remain very good for an entry-luxury drop-top. The G23 carries roughly 350–450 lb of extra structural mass over the coupe and exhibits mild cowl shake and reduced torsional stiffness inherent to any soft-top, so it feels a touch less crisp turn-in and less composed over mid-corner bumps than the coupe.

Same variable-ratio EPS as the coupe: accurate, well-weighted, and consistent, but muted feedback on-center — a small step behind the coupe as the added mass dulls response slightly. Placement remains confident in fast bends.

Firm, linear pedal and strong bite carry over from the coupe, though the ~200–400 lb weight penalty adds a car length or so to instrumented 70-mph stops. Fade resistance remains good in repeated hard use.

Same B48 turbo-four (430i, 255 hp) and B58 turbo-six with 48V mild hybrid (M440i, 382 hp) paired with the ZF 8HP automatic as the coupe — a benchmark drivetrain for tip-in linearity, near-imperceptible shifts, and refined MHEV stop/start. No convertible-specific penalty.

The B58 inline-six sounds excellent with the top down and is nicely isolated with the acoustic soft-top up, though the fabric roof lets a bit more induction and exhaust noise into the cabin than the coupe's fixed steel top. B48 four-cylinder in the 430i is well muted for the class.

BMW USA technical specs for the G23 4 Series Convertible list a curb-to-curb turning diameter of ~39.4 ft (12.0 m), identical to the coupe's wheelbase-driven figure. Long-hood proportions limit tight-quarters maneuverability.

Low, sporty seating position with wide seat/wheel adjustment, supportive standard sport seats, and optional head-up display. Rear three-quarter visibility with the soft-top raised is notably worse than the coupe due to a small rear window and thick fabric quarter panels; top-down visibility is excellent. Curved-display iDrive 8.5 shifts more HVAC/audio controls onto the touchscreen.

Open-air motoring with the B58's rich inline-six soundtrack pushes the enjoyment factor above the coupe despite the modestly softer dynamics; the 430i is still willing and lively. Feels more of a GT-cruiser than a canyon carver, but the drop-top character earns extra 'take the long way home' points.

430i Convertible base includes iDrive 8.5 curved 12.3"+14.9" display, wireless Apple CarPlay/Android Auto, LED headlights, Active Driving Assistant, SensaTec 8-way power sport seats, dual-zone climate, and power soft-top with neck-warmer support — competitive content, but heated seats, Harman Kardon audio, and head-up display still live in the Convenience/Premium packages at a ~$60k base.

The convertible carries a roughly $10k premium over the equivalent coupe for the same B48/B58 turbo powertrains and iDrive 8.5 tech, so bang-for-buck trails the 4 Series Coupe; still, the M440i xDrive Convertible's 382-hp mild-hybrid I6, adaptive M suspension, and AWD around $70k undercut the Porsche 718 and match the fresher Mercedes CLE 450 Cabriolet on content.

Convertible line offers 430i RWD, 430i xDrive, M440i RWD, and M440i xDrive with the M4 Competition xDrive Convertible as a separate halo — same core lineup as the Coupe with two engines and two drive layouts, but no manual gearbox and no plug-in variant limit configurability.

Convertible volume runs a fraction of the 4 Series Coupe's and the premium-droptop segment continues to shrink as Audi exits the US A5 Cabriolet and rivals thin the field — but the 4 Series remains one of the top-selling luxury convertibles alongside the Mercedes CLE Cabriolet, keeping it a steady mid-pack seller in a niche.

BMW ranks top-three in luxury brand desirability with a deep enthusiast following and an open-top halo courtesy of the M4 Competition xDrive Convertible; polarizing vertical kidney grille from the G23 generation slightly offsets the image win but doesn't dent aspirational pull.

BMW Financial Services runs subsidized lease and low-APR programs on 430i and M440i Convertible in most months, and dealer discounts of low-single-digit percent off MSRP are typical — meaningfully better buyer economics than a Porsche 718 or fresh CLE Cabriolet, but far from mainstream-brand rebates.

G23 Convertible launched MY2021 with the switch back to a fabric soft-top and received its LCI mid-cycle refresh for MY2025 (revised front/rear styling, iDrive 8.5 curved display, updated color palette); MY2026 carries that refresh forward with no imminent redesign.

Reviewers praise the M440i xDrive Convertible's B58 straight-six response, chassis balance, and refined open-top experience, but note added weight, mild cowl shake, and a firmer ride versus the Coupe knock a few points off — no 10Best wins for 430i/M440i, but frequent Editor's Choice mentions and favorable comparisons against the Mercedes CLE Cabriolet.