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  • Costco Gasoline
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    Station Operation
    Q: Can anyone buy fuel at a Costco Gas Station?
    A: The Gas Station is open to Costco members only. There is an exception: Costco Cash Card customers do not need to be Costco members.
    Q: Why does the gas station traffic flow only one way?
    A: Costco's approach to gasoline is the same as inside the warehouse - high volume and low prices. One-way traffic makes it easier to get in and out of our stations quickly. Our extra-long hoses allow fueling from either side of the vehicle, so there is no need to be concerned with which lane to choose.
    Q: How do I pay for my gasoline?
    A: The Gas Station is entirely self-serve, with pay-at-the-pump technology. We accept: American Express, most PIN Debit Cards, Costco Credit, and Costco Cash Cards. (Exceptions: Oregon and New Jersey are full-service per law).
    Q: Can I pay with cash or a check?
    A: Cash or checks are not accepted for payment. Eliminating the need for a cashier means a shorter wait for our members. Members may use cash to purchase Costco Cash Cards inside the warehouse.
    Q: Why doesn't Costco accept other major credit cards?
    A: Our exclusive arrangement with American Express helps to assure the lowest transaction fees available, which in turn helps Costco keep prices low.
    Q: How does the pump know the customer is a member?
    A: When a customer inserts a membership card or a co-branded Costco Amex card, the system reads the membership number on the card and confirms the membership is active.

    Costco Cash Cards can only be purchased or recharged by members. Anyone can use a Costco Cash Card at the gas station, as it also serves as membership authorization for the pump.
    Q: Why does Costco "hold" my funds if I use a debit card?
    A: When gasoline is purchased with a PIN debit card, Costco requests a "pre-authorization" before beginning the fueling process. This "pre-authorization" assures that Costco will be paid for the fuel dispensed. The amount "pre-authorized" is the lower of the dollar limit set by the card issuer or $100. After fuel is dispensed, Costco IMMEDIATELY sends a "completion transaction" notice to the card issuer. It is the responsibility of the debit card issuer to reverse the amount that was "pre-authorized" and deduct the actual amount for the fuel purchased as shown on the receipt.

    Please call the customer service number on the back of your debit card if you have questions or concerns.
    Types of Fuel and Fuel Quality
    Q: Is Costco TOP TIER™ certified?
    A: Yes. Both grades of gasoline sold at Costco meet and exceed TOP TIER™ requirements. The owners' manuals provided by the following manufacturers recommend using TOP TIER™ gasoline to maintain optimal engine performance and efficiency.
    • BMW, including Mini Cooper and Rolls-Royce
    • General Motors, including Buick, Cadillac, Chevrolet, and GMC
    • Honda, including Acura
    • Toyota, including Lexus and Scion
    • Volkswagen/Audi, including Porsche, Lamborghini, and Bentley
    • Mercedes-Benz, including Smart
    Q: How does Costco assure their gasoline is high quality?
    A: There are two aspects of fuel quality that depend on the gasoline brand and the individual retailer: deposit control additives and station maintenance.

    Deposit control additives
    Since 1995, Federal regulations mandate that all gasoline contain an EPA-approved deposit control additive. These additives are designed to minimize engine deposits that can affect vehicle performance and emissions. The various proprietary deposit control additive formulations are the main difference between brands of gasoline. All Costco gasoline, both regular and premium unleaded, contains deposit control additives. As of March 2014, all Costco gasoline meets and exceeds TOP TIER™ requirements ( With five times the EPA required amount of additives in our gas, we are proud to call it Kirkland Signature™ Gasoline.

    Station Maintenance
    Good station operation and maintenance means the fuel is filtered and that contaminants, such as sediment and water, do not find their way into our members' vehicles. Costco gas stations are well-maintained by our capable attendants so you may be confident that the gasoline going into your car is clean.
    • Costco uses fuel filters to catch particles or debris larger than 10 microns in diameter. For comparison, the average human hair is seventy microns thick.
    • Our attendants check the nozzle flow rate frequently to assure that our filters are fresh. When the flow rate falls below 8 gallons per minute, we change the filter.
    • Costco uses ethanol-compatible filters designed to catch sediment, water, or phase-separated ethanol and water mixtures.
    • Costco's electronic sensors continuously monitor our underground storage tanks for water.
    • We physically inspect and take chemical samples of our tanks at least weekly to confirm there is no contamination.
    Q: What happened to "Clean Power"?
    A: Although we originally referred to our gasoline additives as Clean Power, we determined that Kirkland Signature™ best describes the high quality and great value of our gasoline. Kirkland Signature™ Gasoline: same quality product, much simpler name.
    Q: What products do you sell?
    A: Regular Unleaded (typically 87 octane) and Premium Unleaded (typically 91 octane). Octane requirements can vary by state.
    Q: Where does Costco get its gasoline?
    A: Costco buys fuel from major refineries and distributors in each area. All Kirkland Signature™ Gasoline is fully guaranteed, just like the merchandise we sell inside the warehouse.
    Q: What is octane, and is that the only difference between regular and premium unleaded gasoline?
    A: Octane is a particular hydrocarbon that is part of all gasoline. The precise amount is determined at the refinery. Octane is not an additive to the fuel. Octane levels are the only difference between regular and premium unleaded gasoline sold at Costco.

    The amount of octane controls how the fuel burns in your engine. Too little octane can cause knocking or pinging, which over time can harm your engine. Knocking and pinging results when the fuel pre-ignites in the cylinder, ahead of the spark plug ignition. Higher octane controls this pre-ignition.
    • Costco advises that you use the octane rating specified in your owner's manual. In fact, using regular unleaded gasoline in a car that specifies premium unleaded could void your vehicle warranty.
    • If you are using the specified fuel, and you are experiencing engine knock, please consult your auto care professional for a diagnosis of the problem.
    Q: Why does Costco gasoline contain ethanol?
    A: The federal Energy Policy Act of 2005 established the Renewable Fuels Standard, which required that a certain amount of ethanol be used in the nations' fuel supply. The Energy Independence and Security Act of 2007 increased this amount. Kirkland Signature™ Gasoline complies with this law, and if our fuel contains ethanol a pump decal will advise you of that fact.
    Q: How safe are Costco Gas Stations?
    A: Costco gas stations have an outstanding safety record. Our safety-certified gas station attendants work outside on the fuel islands, so they are always available to respond to any emergency. Every Costco station is equipped with automatic shut-off mechanisms both above and below ground. All our stations have a dedicated 911 phone, conventional fire extinguishers on every fuel island, and automatic extinguishers below ground. Eye wash is always available as well. Gasoline is highly flammable, and we ask for our members to comply with all applicable laws and signage regarding safe refueling.
    Q: Is it safe for children to pump gas?
    A: No. Children should not pump gas or get out of the car during the refueling process. Costco gas stations are very busy, and children are often below the level of drivers' mirrors. Only licensed drivers should pump gas. Costco gas station attendants are available to assist anyone who requires additional help in filling their tank.
    Q: Why must I shut off my engine while fueling, even when it's very hot or cold outside?
    A: Because it's the law. The national fire code prohibits any potential ignition source, including cigarettes and running engines, while refueling. The national fire code is adopted and enforced by local fire marshals around the country. To comply, all Costco gas stations feature prominent signage advising our members of these rules. All Costco attendants are instructed to enforce the fire code at our gas stations.

    The National Fire Prevention Association (NFPA) code 30A contains the following:
    Sources of Ignition Section 9-7
    Smoking materials, including matches and lighters, shall not be used within 20 feet (6 meters) of areas used for fueling, or receiving or dispensing of Class I liquids. The motors of all equipment being fueled shall be shut off during the fueling operation.
    Q: Is there a risk of static electricity while fueling?
    A: There is a small but real risk of static electricity sparking a gasoline vapor fire at any gas station. To prevent a static discharge from igniting gasoline vapor, always touch your car with your bare hand to discharge any accumulated static energy. If you re-enter your car during refueling, you may accumulate another charge from your vehicle upholstery. Static may be discharged by touching the car or some other metal surface, away from the fill point, each time you exit your vehicle at a gas station. The shock you feel is your protection!

    Static electricity can also accumulate on portable containers transported by a moving vehicle. Accordingly, only approved containers can be filled with fuel, and they must always be removed from the vehicle and placed on the ground before filling. This "grounds" the container and eliminates the static risk.
    Q: Can cell phones ignite a gasoline vapor fire?
    A: No. Cell phones do not produce sufficient voltage to start a gasoline vapor fire. Despite rumors, erroneous emails, and general confusion surrounding this subject, there have been zero confirmed fires caused by cell phones anywhere in the world.

    While the use of a cell phone will not cause a fire, there is a very real concern that talking on a cell phone at a gas station can cause an unrelated accident if you are inattentive to the fueling operation. For your own safety and the safety of those around you, please refrain from using your cell phone while refueling at Costco gas stations.
    Q: What are the rules for filling portable containers at Costco gas stations?
    A: Costco attendants are instructed to enforce all provisions of the International Fire Code (IFC) regarding filling portable containers:

    International Fire Code (IFC) 2012 Edition

    2204.4.1 Approved containers required
    Class I, II and IIIA liquids shall not be dispensed into a portable container unless such container does not exceed a 6-gallon (22.7L) capacity, is listed or of approved material and construction, and has a tight closure with a screwed or spring loaded cover so designed that the contents can be dispensed without spilling. Liquids shall not be dispensed into portable cargo tanks.

    2204.4.2 Nozzle operation
    A hose nozzle valve used for dispensing Class I liquids into a portable container shall be in compliance with section 2206.7.6 and be manually held open during the dispensing operation.

    2204.4.3 Location of containers being filled
    Portable containers shall not be filled while located inside the trunk, passenger compartment or truck bed of a vehicle.