How a U.S. Gas Station Works: From Fuel Delivery to the Pump

A U.S. gas station stores fuel in underground tanks, dispenses it through metered pumps using safety-controlled nozzles, and processes payment via card readers or cash registers, all under environmental, safety, and consumer-protection regulations. In practice, fuel arrives by tanker truck, is monitored for leaks, priced daily based on wholesale costs and taxes, and sold alongside higher-margin convenience items that keep the station profitable.

The fuel supply chain and on-site storage

Gas stations are the last link in a supply chain that begins at refineries or fuel terminals and ends at the dispenser. Most sites are supplied by regional distributors who truck fuel from terminals to stations on fixed or variable schedules, depending on demand and pricing.

Fuel delivery and underground storage tanks (USTs)

Fuel arrives by tanker truck and is unloaded into double-walled underground storage tanks through color-coded fill pipes. Each grade—regular, midgrade, premium—and diesel typically has its own tank; midgrade can also be “blended” at the dispenser by mixing regular and premium. Automatic tank gauges (ATGs) continuously measure volume, temperature, and water presence, and send alerts if levels don’t reconcile with sales, helping detect leaks or delivery errors.

Environmental protection and compliance

UST systems are tightly regulated under federal EPA rules (40 CFR Part 280) and state programs. Newer installations use secondary containment (double walls), sump sensors, overfill prevention devices, spill buckets at fill points, and interstitial monitoring. Operators perform monthly inspections, annual tests of sensors and spill/overfill equipment, and maintain certified Class A/B/C operators. Stage I vapor recovery captures gasoline vapors during deliveries; Stage II recovery at the nozzle has largely been phased out because modern vehicles have onboard vapor recovery systems. Stations keep records for inspectors and insurers, and alarms trigger if fuel or water intrusion is detected.

What fuels are offered

Most stations sell gasoline in 87 (regular), 89 (midgrade), and 91 or 93 (premium) octane; mountain states may offer 85 octane due to altitude, but many automakers advise using at least 87. Diesel is ultra-low sulfur (ULSD, 15 ppm). Ethanol blends include E10 (“up to 10% ethanol”) by default; E15 is permitted for 2001+ light-duty vehicles and is now authorized for year-round sales starting in 2025 in several Midwest states per EPA’s 2024 rule, with temporary summer waivers sometimes issued elsewhere. Flex-fuel pumps (E85) are for flex-fuel vehicles only. Some stations advertise Top Tier detergent gasoline, a performance standard endorsed by many automakers.

At the pump: equipment and payments

Dispenser columns house metering systems, filters, hoses, breakaway couplings, and nozzles. The nozzle’s automatic shutoff uses a vacuum venturi to stop flow when the tank nears full. Hoses are fitted with breakaways to detach safely if a vehicle drives off with the nozzle inserted. An emergency stop switch—typically a red button or switch within sight of the forecourt—cuts power to all pumps in an emergency.

How payment works

Most stations are self-serve, with pay-at-the-pump card readers and an indoor cashier. Card transactions are authorized before fuel flows: the pump requests a temporary hold (often $50–$175+, set by networks/issuers and sometimes higher when prices spike) that is replaced by the actual amount after the transaction settles. Debit holds can differ by bank. EMV chip and contactless payments (tap-to-pay) are widely deployed; since April 2021, stations without EMV at the pump bear fraud liability. Many sites also accept fleet cards, mobile apps, and offer loyalty discounts. Cash purchases typically require prepayment inside. Some stations post a “cash price” with a higher credit price to offset card-processing fees.

What sets the price on the sign

Retail prices reflect wholesale “rack” or contract costs, transportation, federal and state taxes (federal gasoline tax is 18.4¢/gal; diesel 24.4¢/gal; state taxes and fees vary widely), local competition, and credit-card fees. Seasonal gasoline blends and regional environmental rules (e.g., California’s CARB gasoline, reformulated gasoline in some metros) can raise costs, and prices generally move with crude oil and supply/demand conditions. Margins on fuel are thin—often cents per gallon—so stations rely on convenience-store sales for profit.

How to fuel your vehicle

The process is simple, but a few steps help ensure safety, accuracy, and payment success. Follow these steps when you pull up to a pump.

1. Park with your fuel door aligned to the pump and turn off your engine.
2. Select payment method: insert/tap your card at the pump or prepay with cash inside.
3. For card payments, complete prompts (ZIP code, loyalty ID, receipt choice).
4. Select the correct fuel grade for your vehicle and, if applicable, gasoline vs. diesel.
5. Remove the nozzle, insert it fully into the filler neck, and lift the handle to begin fueling.
6. Set the latch if available; stay by the vehicle while fueling. The nozzle will auto-shutoff near full.
7. After fueling, return the nozzle, close your fuel door, collect your receipt, and verify the charge later when the hold releases.

These steps minimize spills, ensure you purchase the correct fuel, and reduce hassles related to payment holds or errors.

Safety, etiquette, and accessibility

Gasoline is flammable and its vapors are hazardous; simple precautions greatly reduce risk. Keep these practices in mind every time you refuel.

• No smoking, vaping, or open flames; turn off the engine.
• Discharge static by touching metal before handling the nozzle; avoid re-entering the vehicle while fueling.
• Do not top off after the first click-off; this can spill fuel and damage vapor systems.
• Use only the correct fuel—diesel nozzles are usually larger and labeled; E85 is for flex-fuel vehicles only.
• Know the location of the emergency stop and fire extinguishers.
• Clean minor spills with station absorbent; alert staff for larger spills or any fumes/fire risk.
• Be mindful of others: pull forward after fueling, and don’t block pumps if going inside.

Following these norms protects you and others, prevents equipment damage, and keeps traffic moving safely through the forecourt.

Security and fraud prevention

Payment-card skimming at pumps has declined with EMV chip adoption but still occurs, especially at older dispensers. A few checks can lower your risk.

• Prefer pumps in the cashier’s line of sight and look for intact tamper-evident seals.
• Use chip or contactless payments; avoid swiping if the chip reader is present.
• Cover the keypad when entering PINs and avoid public Wi‑Fi if using a station app.
• Monitor your account; temporary holds should clear to the final amount within 1–3 business days.

Staying vigilant and using secure payment methods reduces the chance of card compromise and simplifies dispute resolution if issues arise.

State-by-state differences you might notice

Gas station operations follow national norms but some rules vary by state and locality.

Self-serve vs. full-serve

Most states are self-service. New Jersey remains the only state that still prohibits self-serve statewide, requiring attendants to pump fuel. Oregon, which historically restricted self-serve, legalized self-service statewide in 2023 with conditions: in more populous counties, at least half of a station’s pumps must remain attendant-operated and pricing must be the same for both options. Some municipalities elsewhere have local rules on hours or signage.

Fuel blends and seasonal rules

Summer gasoline has lower volatility to reduce smog, which can change costs and availability. Certain metro areas require reformulated gasoline. E15 year-round sales begin in 2025 in several Midwest states per EPA’s 2024 rule; elsewhere, E15 availability can depend on seasonal waivers. California’s Low Carbon Fuel Standard and unique gasoline formulation often make prices higher than the U.S. average. In California, stations must provide free air and water to fuel purchasers upon request.

What else happens behind the scenes

Convenience stores drive profitability: beverages, snacks, coffee, prepared food, lottery, and car washes have higher margins than fuel. Many locations are branded (Shell, Exxon, BP, Chevron, etc.) but locally owned, operating under supply agreements that influence pricing and promotions. Stations maintain canopy lighting, cameras, and spill kits; schedule periodic tank tightness tests; and coordinate hazardous waste disposal for contaminated absorbents. Accessibility policies typically include posting a phone number or using a call button; under ADA guidance, stations that offer self-serve are expected to assist disabled drivers with refueling at self-serve prices when staff are on duty.

Summary

A U.S. gas station stores multiple fuel grades in regulated underground tanks, dispenses them through safety-engineered pumps, and processes payments that often involve temporary card holds. Prices reflect wholesale costs, taxes, local competition, and fees, while profits usually come from in-store sales. Rules vary by state—especially on self-serve and fuel blends—but the core operation is consistent: safe storage, accurate metering, compliant vapor and leak controls, and a quick, secure customer experience at the pump.

How do they pay for gas in the USA?

When filling up with petrol (or pumping gas) in the US you must first, either swipe your credit card or go inside and leave cash with the attendant. If you use a preloaded money card or debit card just be aware the hold amount may be held for several days.

How do US gas stations work?

Activates. And starts sending gas up through a series of pipes. And filters into the fuel. Dispenser.

How to pay at a gas station in the USA?

Once you pull up to the pump (make sure you’re close enough for the hose to reach your tank!), it’s time to insert your credit or debit card into the machine. Most machines will ask you to remove your card again right away, but newer machines require leaving your card in longer, so pay attention to the directions.

How often does a gas station get refilled?

How often do gas stations refill? Some gas stations may refill their tanks once or even multiple times per day. However, this depends on the volume of fuel that they sell.