Best Automotive Relays Under $25 (2026): 5 Relay Kits Compared

A horn that stays silent, a fan that never kicks on, lights that flicker when the switch is flipped: small electrical faults like these often point to a tired relay rather than a failed part. Swapping the relay is a small garage job, but the replacement has to match the pins, the rating and the wiring. This guide compares the best automotive relays under 25, looking only at what each listing states about pins, rating, harness and warranty.

GarageToolHQ earns a commission when you buy through links on this page, at no extra cost to you. Read our affiliate disclosure.

Picks for the garage

#	Product	Shop Score	Buy
1	Nilight 10 Pack SPDT 5PIN Electrical Relays 12V	9.6/10	Buy on Amazon
2	True MODS 6 Pack Bosch Style 4-Pin 12V Fused Relay	9.5/10	Buy on Amazon
3	12VDC 30A 5-pin Multi-Purpose Starter Relay	9.5/10	Buy on Amazon
4	Ronybuy 5-Pin Waterproof Relay Kit 40/30 AMP 12V	9.4/10	Buy on Amazon
5	40/30AMP 12VDC Waterproof 4-pin Automotive Relays	9.4/10	Buy on Amazon

1

Nilight 10 Pack SPDT 5PIN Electrical Relays 12V

Nilight·9.6/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A 10-pack of 5-pin SPDT relays rated 12V and 30/40 amp, with a maximum operating voltage of 27VDC, a must operate voltage of 6~8 VDC, coil power of 1.8W, coil resistance of 80 Ω, and a stated 2 Years Warranty.

Check price on Amazon

Pros

• 10 relays in the pack, the most here
• Fullest coil specs stated: voltage, power and resistance
• 5-pin SPDT form for two-way switching circuits
• Stated 2 Years Warranty, the longest here

Cons

• Spec table lists 1 item while the title says a 10-pack
• No harness or socket stated in the listing
• No waterproof rating stated
• No fuse stated in the pack

2

True MODS 6 Pack Bosch Style 4-Pin 12V Fused Relay

ONLINE LED STORE·9.5/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A 6-pack of Bosch style 4-pin SPST relays rated 12 volt and 30 amp, each with an interlocking harness socket, a built-in fuse socket with an included 30A blade fuse, and 14 AWG wires.

Check price on Amazon

Pros

• Built-in fuse socket with an included 30A blade fuse
• Complete kit: 6 relays, 6 harnesses and 6 fuses
• Interlocking harness sockets stated
• Pinout stated: 85 ground, 30 VDC, 86 trigger, 87 output

Cons

• No warranty term stated in the listing
• SPST only, with no 87a normally-closed output
• No waterproof rating stated
• No coil resistance or power stated

3

12VDC 30A 5-pin Multi-Purpose Starter Relay

iRhapsody·9.5/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A pack of 8 plug-and-play 5-pin relays rated 12VDC and 30A, listed for lawnmowers and cars, with dimensions of 1.5 inches by 0.94 inches by 0.66 inches, and a stated one-year warranty.

Check price on Amazon

Pros

• 8 relays in the pack, for spares across vehicles
• Plug-and-play style, per the listing
• Compact size stated in the spec table
• Stated one-year warranty

Cons

• No coil resistance or power stated
• No harness or socket stated
• No waterproof rating stated
• Fitment stated only in general terms, with no model list

4

Ronybuy 5-Pin Waterproof Relay Kit 40/30 AMP 12V

Ronybuy·9.4/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A 2-pack of 5-pin SPDT relay kits rated 12VDC and 40A/30A with harness, 12 AWG and 16 AWG tinned copper wires, and an IP65 waterproof shell, per the listing.

Check price on Amazon

Pros

• IP65 waterproof shell with sealed terminals and rubber ring
• Color-coded harness wires with pin colors stated
• 5-pin SPDT form with both 87 and 87a outputs
• Listed for horns, starters, fans, boats and more

Cons

• No warranty term stated in the listing
• Only 2 kits in the pack
• Listing recommends professional technicians for installation
• No coil resistance or power stated

5

40/30AMP 12VDC Waterproof 4-pin Automotive Relays

iRhapsody·9.4/10 Shop Score

i

The Shop Score runs from 9.2 to 9.8 and weighs performance (35%), build (25%), value (25%), safety (10%, where it applies) and warranty (5%), using only what the manufacturer and the listing publish. How we pick ›

A 2-pack of 4-pin 12VDC relays rated 40/30 amp with a built-in diode, 12 AWG tinned copper primary leads and 16 AWG coil leads of 7 inches, and a stated One-year warranty.

Check price on Amazon

Pros

• Built-in diode, per the title
• 12 AWG tinned copper primary leads stated
• Water-repellent and dustproof ability stated in the bullets
• Stated One-year warranty

Cons

• Title says waterproof but bullets say not to use it in water
• Listing warns it might be too big for some applications
• Only 2 relays in the pack
• Pin polarity is fixed: 86 to positive, 85 to negative, per the listing

Compared on paper

These numbers are the tool makers’ rated figures, as their listings print them on 30 October 2026. “Not stated” means the listing does not give the figure. Pin numbers follow the listing diagrams: 85 ground, 86 trigger, 30 power, 87 output, and 87a where a 5-pin relay states it.

How the points were given

Each relay is scored on performance, build, value, safety and warranty, using only what the listing publishes. None of the five listings states an electrical safety listing, so every relay scores zero for safety, which pulls all scores down equally.

We map each tool’s weighted total onto a 9.2 minimum and 9.8 maximum in a straight line, so the point order and score order match.

Best automotive relays under 25: buying guide

Pins and poles

Four-pin relays here are SPST, with a single output on pin 87. Five-pin relays are SPDT, adding a normally-closed output on pin 87a, which the Ronybuy listing wires in yellow. Match the pin count to the socket first: a 5-pin relay will not suit a 4-pin socket, and a 4-pin relay cannot give the second output a 5-pin circuit expects.

Rating and headroom

Ratings here run from 30A to 40A/30A depending on the listing. Two listings advise staying 10 to 15% below the rated value, so size the relay above the circuit load rather than exactly at it. The Nilight listing gives the fullest electrical picture, with a maximum operating voltage of 27VDC and a must operate voltage of 6~8 VDC alongside its 12VDC normal coil voltage.

Harness, fuse and wire

Only two picks arrive as harness kits. The True MODS kit adds a fused socket with an included 30A blade fuse and 14 AWG wires, while the Ronybuy kit wires its harness in 12 AWG and 16 AWG tinned copper with color-coded leads. The Nilight and iRhapsody 8-pack listings state relays only, with no harness or socket stated, so plan on reusing the existing socket or sourcing one.

Pack size and spares

Pack sizes run from 2 relays to 10 relays, and a spare relay in the drawer is good cover against the next silent horn or dead fan. The Nilight 10-pack and the iRhapsody 8-pack suit a garage that services more than one vehicle, while the 2-packs suit a single known job with one spare left over.

Warranty

Only three listings state a warranty term: Nilight states 2 Years Warranty, and both iRhapsody listings state a one-year warranty. The Ronybuy and True MODS listings state no warranty term, so those two score zero for warranty here even though their kits look complete.

Garage Fit Check

• Check pin count and pole type against the old relay and the socket before ordering.
• Match the rating to the circuit, and keep the load below the rated value as the listings advise.
• Confirm the relay fits the space available: the diode pair listing warns it might be too big for some applications.
• For wiring beyond a straight swap, the Ronybuy listing recommends professional technicians.

FAQ: garage tools

What do 4-pin and 5-pin relays do differently?

A 4-pin SPST relay switches a single output on pin 87. A 5-pin SPDT relay adds a normally-closed output on pin 87a, so it can switch between two circuits instead of simply switching one on and off.

What rating do I need?

Match the rating to the circuit the relay will switch, and keep the load below the rated value as the listings advise. Two listings here advise staying 10 to 15% below the rated value.

Do I need a harness or fuse?

It depends on the pick. The True MODS kit includes harness sockets and a 30A blade fuse for each relay, and the Ronybuy kit includes a wired harness. The Nilight and iRhapsody 8-pack listings state relays only, with no harness stated.

Are these relays waterproof?

Only the Ronybuy kit states an IP65 waterproof shell with sealed terminals. The iRhapsody diode pair listing calls itself water-repellent and dustproof but says not to use it in water, and the other listings state no waterproof rating.

What warranty do these relays carry?

Nilight states a 2 Years Warranty, and both iRhapsody listings state a one-year warranty. The Ronybuy and True MODS listings state no warranty term.

More garage guides

See the diagnostics and electrical hub, the best automotive relay box kit, the best automotive relay removal tool, and the best automotive relays guide for the wider field.