# Narrow convertible car seats for small back seats
Which convertible car seats are narrow enough for a small back seat?
Graco SlimFit3 LX: At 16\.7 inches wide, the reviewer calls it one of the narrowest convertible car seats and says if it does not fit a tight setup, likely nothing else will\. The seat is about 16\.7 inches wide at the shoulders, with a base about 11\.5 inches wide, making it one of the narrowest convertible seats tested\. Graco confirmed that three SlimFit3 LX seats fit three\-across in a 2019\-2021 Toyota RAV4 in several configurations, including all forward\-facing, all rear\-facing, and mixed modes\. Diono Radian 3RXT Safe\+ Max: Unfolded, the seat measures 16 in wide, 17 in deep and 28\.5 in high\. Evenflo All4Stages Slim 4\-in\-1 Convertible Car Seat: 16\.9 in\. family cars or rentals Britax \(listed by the store as Britax\-dc\) One4Life Slim ClickTight All\-in\-One Car Seat, SKU E1D407A\-OB: The seat is 17\.5 inches wide, described as slim enough to fit three across in most vehicles\. Graco SlimFit 3\-in\-1 Narrow All\-in\-One Convertible Car Seat \- Sydney: The original SlimFit was introduced to solve back\-seat space problems and is described as narrow and affordable\. The rotating cupholders can be turned to reduce the seat's width\.
### 1. [Graco SlimFit3 LX](/products/ucp/albeebaby-com/9685796585703) (sold by albeebaby\.com)
At 16\.7 inches wide, the reviewer calls it one of the narrowest convertible car seats and says if it does not fit a tight setup, likely nothing else will\.
- Width: The seat is about 16\.7 inches wide at the shoulders, with a base about 11\.5 inches wide, making it one of the narrowest convertible seats tested\. (review)
- Modes: The seat grows from a rear\-facing harness to a forward\-facing harness to a highback booster\. (listing)
- Weight: The reviewer measured the seat at about 18 pounds\. (review)
- Fit in car: Graco confirmed that three SlimFit3 LX seats fit three\-across in a 2019\-2021 Toyota RAV4 in several configurations, including all forward\-facing, all rear\-facing, and mixed modes\. (blog)
### 2. [Diono Radian 3RXT Safe\+ Max](/products/ucp/megababiesusa-com/8656540500222) (sold by megababiesusa\.com)
Unfolded, the seat measures 16 in wide, 17 in deep and 28\.5 in high\.
- Width: Unfolded, the seat measures 16 in wide, 17 in deep and 28\.5 in high\. (guide)
- Modes: -
- Weight: The seat itself weighs 30\.6 lb\. (guide)
- Fit in car: -
### 3. [Evenflo All4Stages Slim 4\-in\-1 Convertible Car Seat](/products/ucp/evenflo-com/8602499711132) (sold by evenflo\.com)
16\.9 in\.
- Width: 16\.9 in\. (listing)
- Modes: from birth to booster (listing)
- Weight: 23\.6 lbs (listing)
- Fit in car: family cars or rentals (listing)
### 4. [Britax \(listed by the store as Britax\-dc\) One4Life Slim ClickTight All\-in\-One Car Seat, SKU E1D407A\-OB](/products/ucp/albeebaby-com/9564436201703) (sold by albeebaby\.com)
The seat is 17\.5 inches wide, described as slim enough to fit three across in most vehicles\.
- Width: The seat is 17\.5 inches wide, described as slim enough to fit three across in most vehicles\. (listing)
- Modes: The seat is an all\-in\-one that converts to a booster and is stated to fit a child from 5 to 120 lb and up to 63 inches tall\. (listing)
- Weight: -
- Fit in car: -
### 5. [Graco SlimFit 3\-in\-1 Narrow All\-in\-One Convertible Car Seat \- Sydney](/products/ucp/albeebaby-com/9564479750375) (sold by albeebaby\.com)
The original SlimFit was introduced to solve back\-seat space problems and is described as narrow and affordable\.
- Width: -
- Modes: It is a 3\-in\-1 all\-in\-one convertible car seat that can be used rear\-facing, forward\-facing, and as a belt\-positioning booster\. (listing)
- Weight: -
- Fit in car: The rotating cupholders can be turned to reduce the seat's width\. (review)
## Also cited in the text
- Graco SlimFit 3\-in\-1 Narrow All\-in\-One Convertible Car Seat \- Sydney, purpose: The original SlimFit was introduced to solve back\-seat space problems and is described as narrow and affordable\. (blog)
- Graco SlimFit3 LX, narrowness: At 16\.7 inches wide, the reviewer calls it one of the narrowest convertible car seats and says if it does not fit a tight setup, likely nothing else will\. (blog)
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Written 2026-10-27T03:10:46.604Z.
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