Where Is the Cheapest Place to Buy Auto Parts Online in the US (2026)?
The cheapest place to buy auto parts online in the US is usually eBay for used, OEM-surplus and aftermarket parts, or Walmart.com for everyday maintenance parts with store pickup. Confirm fitment by part number, compare the delivered price, then go through ShopBack before you pay.
Published: 8 October 2026 · Last updated: 8 October 2026 · Author: Ziling Liu, Personal Finance Editor, ShopBack
In the US in 2026, the cheapest place to buy auto parts online is usually eBay for used, OEM-surplus and aftermarket parts, or Walmart for everyday maintenance parts such as wipers, filters, oil and batteries with free store pickup. The cheapest part is the one that fits your exact vehicle, so match the part number first, compare the delivered price, then go through ShopBack before you pay.
The numbers that matter: according to the US Bureau of Labor Statistics, the consumer price index for motor vehicle parts and equipment was 188.873 in August 2026, compared with 187.124 in August 2025, a rise of about 0.9%. Walmart+ costs $98 a year or $12.95 a month, according to published details of the program, and includes free shipping on items sold or shipped by Walmart.com.
ShopBack US is a cashback site for shoppers in the United States. Going through ShopBack gets you a cash rebate on the same order, at the same store. You can sign up for ShopBack in a couple of minutes before your next order.
Where is the cheapest place to buy auto parts online?
There is no single cheapest site for every part. The cheapest place is the one with the lowest delivered price for the exact part number that fits your car. For most US drivers, that comes down to two kinds of store:
- eBay for parts with many sellers. eBay lists new, used, remanufactured and OEM-surplus parts from many sellers, so popular part numbers often have several competing listings. It is often a good source for older cars, body panels, trim, mirrors, lights and hard-to-find parts that local stores do not stock.
- Walmart.com for everyday maintenance. Walmart sells wipers, filters, motor oil, bulbs, batteries and accessories, and many Walmart stores have an Auto Care Center. Ordering online for store pickup avoids shipping on bulky or heavy items.
The quick rule: for a used, rare or body part, start on eBay; for routine maintenance items you need this week, start on Walmart.com; for anything in between, compare the same part number at both on the same day.
Other places that sell auto parts online in the US include auto parts chains such as AutoZone, Advance Auto Parts and O'Reilly Auto Parts, online specialists such as RockAuto and CarParts.com, and warehouse clubs Costco and Sam's Club for tires and batteries, the last two on ShopBack US.
Auto parts online: how to make sure the part fits
A cheap part that does not fit costs you return shipping, time and sometimes a second tow. Check fitment before you compare prices.
Use the part number. Year, make and model is not enough, because trims, engines and mid-year changes use different parts. The OEM part number is often stamped on the old part, and a dealer parts counter can look it up from your VIN (vehicle identification number). Search that exact number.
Use the vehicle selector, then confirm. eBay and Walmart.com both let you save or enter your vehicle to filter parts. Use it, then confirm that the part number in the listing matches yours.
Check the side and position. Many parts come in left and right, or front and rear, versions. In the US, the "driver side" is the left side.
Know the core charge. Parts such as batteries, alternators and starters often carry a refundable core charge to encourage you to return the old part. You usually get it back when you return the core, so leave it out of the comparison, but do return the core.
OEM vs aftermarket vs used: what each costs you
| Type | What it is | Usually cheapest at | Best for |
|---|---|---|---|
| OEM | Made by or for the car maker | eBay (OEM-surplus listings) | Sensors, electronic modules, exact-fit trim |
| Aftermarket | Made by another manufacturer to fit | eBay and Walmart.com | Brakes, filters, wipers, lights, suspension |
| Used or recycled | Pulled from another vehicle | eBay | Body panels, mirrors, interior trim, older cars |
| Remanufactured | Used part rebuilt to spec | eBay and parts specialists | Alternators, starters, steering racks |
Does aftermarket void the warranty? Usually not by itself. Under the federal Magnuson-Moss Warranty Act of 1975, warrantors generally cannot make a written warranty depend on you using a specific brand of parts, with some exceptions, according to the FTC's guide to federal warranty law. A part that causes damage can still affect a claim, so keep receipts and check your warranty booklet.
Safety parts. For brakes, steering and suspension, many drivers buy new parts from known brands even when a used one is cheaper.
Auto parts online in 2026: what prices are doing
Parts prices have been fairly flat on average in 2026. According to the US Bureau of Labor Statistics, the consumer price index for motor vehicle parts and equipment was 188.873 in August 2026, compared with 187.124 in August 2025, a rise of about 0.9%. Earlier in 2026 the index moved between 186.920 (January) and 189.059 (March).
The average hides big differences between parts. Two sellers can list the same part number far apart in price, which is why comparing the delivered price for the same number matters more than waiting for the market to move.
Auto parts online: best deals in the US for 2026
Auto parts deals in the US are most likely during:
- Black Friday and Cyber Monday. Black Friday 2026 is Friday, November 27, and Cyber Monday is November 30. Auto products often appear in store-wide sales that week at both eBay and Walmart.
- Before winter. Wipers, batteries and lights fail more often in cold, dark months. Replacing worn items during a fall sale is usually cheaper than paying full price after a failure.
- Any time on eBay. Because many sellers list the same part, prices move every day. Saved searches for your part number help you catch a lower listing.
The most expensive part is the one you buy in a hurry. For routine maintenance items, keep a short list and buy during a sale.
eBay vs Walmart auto parts online: price comparison in 2026
eBay and Walmart are both on ShopBack US, and both are good places to buy auto parts online, for different jobs. Compare the delivered price for the same part number at both on the same day.
Where eBay is strong. Many sellers compete on the same part, so popular and older part numbers often have several prices to choose from. eBay is one of the largest places to find used and OEM-surplus parts online. eBay's Money Back Guarantee covers eligible purchases that do not arrive or do not match the listing; read eBay's own terms for which parts and listings qualify. Shipping cost varies by seller, so compare the price including shipping.
Where Walmart is strong. Walmart.com is easiest for everyday maintenance parts you want this week, with store pickup at many locations. Walmart+ costs $98 a year or $12.95 a month and, according to published details of the program, includes free shipping on items sold or shipped by Walmart.com, a fuel discount of 10 cents a gallon at participating stations, and free flat tire repair and a road hazard warranty at Walmart Auto Care Centers.
| eBay | Walmart.com | |
|---|---|---|
| Best for | Used, OEM-surplus, rare and body parts | Wipers, filters, oil, bulbs, batteries, accessories |
| How price is set | Many sellers compete on the same part number | Walmart and marketplace sellers |
| Getting the part | Shipped by the seller | Shipping or store pickup at many locations |
| Membership | None needed | Walmart+ optional at $98 a year or $12.95 a month |
| Protection | eBay Money Back Guarantee on eligible purchases | Walmart's return policy; check marketplace seller terms |
eBay and Walmart: the official programs that lower the price
eBay. eBay lets you save your vehicle so listings filter to parts that fit, and some parts listings carry fitment information from the seller. eBay's Money Back Guarantee covers eligible purchases. Check eBay's own pages for the current terms, including which listings and parts qualify.
Walmart+. Walmart's paid membership costs $98 a year or $12.95 a month. For drivers, the useful parts are free shipping on Walmart.com items, the fuel discount at participating stations and the Auto Care Center perks. For a single part it is unlikely to pay for itself; for a household that already orders from Walmart often, it can.
Where ShopBack fits before you buy auto parts online
Going through ShopBack gets you a cash rebate on the same order, at the same store. Cashback lowers what you actually pay for an order. It comes back as cash, so it works like a discount on the price, not like points or miles.
The routine that gets the lowest price:
- Step 1: compare prices. Search the exact part number on eBay and Walmart.com and compare the delivered price.
- Step 2: look for a promo code. Use one featured on the store's ShopBack page, because codes from other sites can stop an order from tracking.
- Step 3: go through ShopBack. Open the store's page on ShopBack US and tap through to the store.
- Step 4: pay with your best rewards card, in the same session.
Illustrative example: at a store that pays a percentage, on a $200 order of brake pads and rotors at an illustrative 3%, $6 comes back, so the effective price is $194. Walmart works differently: ShopBack pays a fixed cash amount on eligible Walmart orders, so your effective price is what you pay at checkout minus that amount; the live amount is on Walmart's ShopBack page. The real rate or amount is different for each store and category and changes over time, so check it on each store's ShopBack page: eBay and Walmart.
Each store has its own terms, and for auto parts they matter:
- eBay. Some categories and listing types can be treated differently. Read the Terms section on ShopBack's eBay page before you count on cash back for a parts order.
- Walmart. Read the Terms section on ShopBack's Walmart page, including how marketplace items are treated.
- In-store purchases. A part bought at the counter without an online order does not go through ShopBack. Order online first, then pick up.
Paying with a rewards card
A rewards credit card is your own program with your card issuer, and it usually earns its own points or cash back as normal on an order you started on ShopBack. Check the merchant's terms on its ShopBack page for any payment methods that are excluded, and check your card issuer's terms for how auto parts purchases are categorised. Paying off the balance in full keeps interest from wiping out what you saved.
Frequently asked questions
Where is the cheapest place to buy auto parts online?
In the US, the cheapest place to buy auto parts online is usually eBay for used, OEM-surplus and aftermarket parts, or Walmart.com for everyday maintenance parts such as wipers, filters, oil and batteries with free store pickup. The cheapest part is the one that fits your exact vehicle, so match the part number first, compare the delivered price, then go through ShopBack before you pay.
Is eBay or Walmart cheaper for auto parts?
It depends on the part. eBay is often cheaper on used, hard-to-find and OEM-surplus parts because many sellers compete on the same part number. Walmart.com is often cheaper on everyday maintenance items, where you can pick up in store and avoid shipping. Compare the delivered price for the same part number on the same day.
Are OEM or aftermarket parts cheaper?
Aftermarket parts are usually cheaper than OEM (original equipment manufacturer) parts. For wear items such as brake pads, filters and wipers, a reputable aftermarket brand is usually fine. For sensors and electronic modules, many drivers prefer OEM for fit and reliability.
Will using aftermarket parts void my car warranty?
Usually not by itself. Under the federal Magnuson-Moss Warranty Act of 1975, warrantors generally cannot make a written warranty depend on you using a specific brand of parts, with some exceptions, according to the FTC. A part that causes damage can still affect a claim, so check your car's warranty booklet.
How do I make sure an auto part fits my car?
Match the part number, not just the year, make and model. Find the OEM part number on the old part or from a dealer parts counter using your VIN, then search that number. Most parts sites also have a vehicle selector; use it, then confirm the part number on the listing.
Is it safe to buy used auto parts on eBay?
Usually, for body, trim and many mechanical parts, if you check the seller's feedback, photos, part number and return policy. eBay's Money Back Guarantee covers eligible purchases that do not arrive or do not match the listing; read eBay's own terms for which parts qualify. Many drivers buy safety parts such as brakes new.
Are auto parts getting more expensive in 2026?
Only slightly on average. According to the US Bureau of Labor Statistics, the consumer price index for motor vehicle parts and equipment was 188.873 in August 2026, compared with 187.124 in August 2025, a rise of about 0.9%. Prices for individual parts vary much more than the average.
Does Walmart+ help with car costs?
It can if you already shop at Walmart. Walmart+ costs $98 a year or $12.95 a month and includes free shipping on items sold or shipped by Walmart.com, a fuel discount of 10 cents a gallon at participating stations, and free flat tire repair at Walmart Auto Care Centers, according to published details of the program. Check Walmart's own Walmart+ page for the current list.
When are auto parts cheapest online?
Auto parts often appear in store-wide sales around Black Friday (November 27, 2026) and Cyber Monday (November 30, 2026). For routine items such as wipers, filters and oil, buying ahead during a sale is usually cheaper than buying in a hurry.
How does ShopBack make auto parts cheaper?
Going through ShopBack gets you a cash rebate on the same order, at the same store. At a store that pays a percentage, a $200 parts order at an illustrative 3% brings $6 back, so the effective price is $194. ShopBack pays a fixed cash amount on eligible Walmart orders instead, so your effective price there is what you pay at checkout minus that amount. Check the live rate or amount and terms on the store's ShopBack page on the day you buy.
Is cashback the same as reward points?
No. Cashback lowers what you actually pay for an order. It comes back as cash, so it works like a discount on the price, not like points or miles.
Key takeaways
- The cheapest place to buy auto parts online in the US is usually eBay for used, OEM-surplus and rare parts, or Walmart.com for everyday maintenance items with store pickup.
- Match the exact part number, not just the year, make and model, and compare the delivered price.
- Parts prices rose about 0.9% from August 2025 to August 2026 on average, according to the BLS, so the seller matters more than the timing.
- Walmart+ is $98 a year or $12.95 a month and includes Auto Care Center perks, according to published details of the program.
- Compare prices, find a promo code, go through ShopBack, then pay with your best rewards card.
Sub-guides
- Where Is the Cheapest Place to Buy a Car Battery in the US?
- Walmart Discounts in the US
- Do Coupon Codes Actually Work? Where to Find Ones That Work
Related reads
Shop auto parts on ShopBack US: eBay · Walmart · Costco · Sam's Club
Disclaimer
The views and recommendations expressed in this article are those of the author. Part prices, fitment, seller terms, return policies, membership fees, store programs and ShopBack terms vary by store and over time and are subject to change. Cashback rates on ShopBack vary by store and campaign; check the current rate and terms on each store's ShopBack page before you buy.
This article is intended for general informational purposes only and should not be considered professional, mechanical, legal or financial advice.
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