2015-2021 WRX STI Sway Bars

Sway bars (anti-roll bars) are the best handling value on a 2015-2021 WRX STI. They reduce body roll in corners without changing ride height or spring rates, which means your daily ride comfort stays essentially untouched while cornering flattens out noticeably. For a street car, they are often a smarter first suspension mod than coilovers.

Front versus rear matters for balance. A stiffer rear bar reduces understeer and makes the car rotate more willingly — the classic WRX STI improvement. A stiffer front bar adds stability but increases understeer. Most drivers start with the rear bar, then add the front if they want a more neutral balance. Adjustable bars with multiple end-link holes let you fine-tune stiffness without buying another bar.

Diameter is not the whole story — the bar's material, solid versus hollow construction, and mounting hardware all affect effective rate. Hollow bars save weight with similar stiffness. Make sure the kit includes upgraded bushings and brackets; the factory mounts can flex or fail with a much stiffer bar.

Pair sway bars with quality end links to remove slop from the factory links. Filter by front/rear position and adjustability to dial in your 2015-2021 WRX STI.

In Stock

Whiteline 15-21 STI Sway Bar Kit 26mm Front Adjustable / 22mm Rear Adjustable w/ Endlinks | BSK019

Only 3 left

Regular price $905.88

Sale price $905.88 Regular price ~~$905.88~~
Unit price per
Up to $102 off

Perrin Rear Adjustable Sway Bar - 16mm
Fits: 08-21 WRX, 08-21 STI, 13-23 BRZ, 13-16 FR-S, 17-21 GT86, 22-23 GR86

Regular price $178.00

Sale price $178.00 Regular price ~~$280.00~~
Unit price per
Up to $118 off

Perrin Rear Adjustable Sway Bar 19mm
Fits: 08-21 WRX/STI, 13-23 BRZ, 13-16 FRS, 17-21 GT86, 22-23 GR86

Regular price $204.00

Sale price $204.00 Regular price ~~$322.00~~
Unit price per
Up to $64 off

Perrin Rear Adjustable Sway Bar 25mm
Fits: 08-21 WRX/STI, 13-16 FR-S, 13-20 BRZ, 17-20 86, 22-26 BRZ/GR86

Regular price $274.00

Sale price $274.00 Regular price ~~$338.00~~
Unit price per
Up to $32.79 off

In Stock

Whiteline Front Sway Bar 27mm Adjustable
Fits: 15-21 STI

Regular price $295.09

Sale price $295.09 Regular price ~~$327.88~~
Unit price per
Up to $49.50 off

Perrin Rear Adjustable Sway Bar 22mm
Fits: 08-21 WRX/STI, 13-16 FR-S, 13-20 BRZ, 17-20 86, 22-26 BRZ/GR86

Regular price $280.50

Sale price $280.50 Regular price ~~$330.00~~
Unit price per
Up to $35 off

In Stock

Cusco Rear Sway Bar 22mm | 6A1-311-B22
Fits: 15-21 WRX/STI

Only 5 left

Regular price $315.00

Sale price $315.00 Regular price ~~$350.00~~
Unit price per
Up to $24.50 off

In Stock

Cusco Rear Sway Bar Reinforcement Brace | 6A1-492-RL
Fits: 15-21 WRX/STI

Only 5 left

Regular price $220.50

Sale price $220.50 Regular price ~~$245.00~~
Unit price per
In Stock

Kartboy Front & Rear Swaybar Endlink Combo
Fits: 15-21 WRX/STI

Regular price $276.00

Sale price $276.00 Regular price ~~$276.00~~
Unit price per
Up to $50.40 off

In Stock

Perrin Front Sway Bar - 26mm
Fits: 15-21 STI

Only 7 left

Regular price $285.60

Sale price $285.60 Regular price ~~$336.00~~
Unit price per
FactionFab Solid End Link Set - Front
Fits: 15-21 WRX/STI

Regular price $125.00

Sale price $125.00 Regular price ~~$125.00~~
Unit price per
Perrin Rear Sway Bar - 22mm
Fits: 13-20, 22-26 BRZ, 22-26 GR86, 08-21 WRX, 08-21 STI, 13-16 FR-S, 17-20 86, 09-15 Forester, 13-17 Crosstrek/XV, 08-14 Impreza, 10-14 Legacy

Regular price $309.40

Sale price $309.40 Regular price
Unit price per
Perrin Rear Sway Bar - 18mm
Fits: 13-20, 22-26 BRZ, 22-26 GR86, 08-21 WRX, 08-21 STI, 13-16 FR-S, 17-20 86, 09-15 Forester, 13-17 Crosstrek/XV, 08-14 Impreza, 10-14 Legacy

Regular price $303.88

Sale price $303.88 Regular price
Unit price per
Perrin Rear Sway Bar - 16mm
Fits: 13-20, 22-26 BRZ, 22-26 GR86, 08-21 WRX, 08-21 STI, 13-16 FR-S, 17-20 86, 09-15 Forester, 13-17 Crosstrek/XV, 08-14 Impreza, 10-14 Legacy

Regular price $303.88

Sale price $303.88 Regular price
Unit price per
In Stock

Cobb Tuning Sway Bar Package
Fits: 15-21 STI, 18 Type RA, 19 S209

Only 3 left

Regular price $1,170.00

Sale price $1,170.00 Regular price ~~$1,170.00~~
Unit price per
Cusco 15-21 STI Front Sway Bar 26mm | 6A1-311-A26

Regular price $312.30

Sale price $312.30 Regular price ~~$312.30~~
Unit price per