A points-and-miles expert who got a tank of gas for 38 cents shares exactly which credit card to open if you want to fill up for less

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Richard Kerr is an award travel expert. A US Navy veteran, Kerr learned about using credit card points and frequent-flyer miles while he was in the service, looking for more affordable ways to travel home during leave.

Business Insider recently spoke with Kerr - now a full-time educator, writer, and podcaster focusing on the world of "travel hacking" -who offered advice on everything from racking up credit card points to use for free flights, to finding deep discounts at hotels.

Some of his suggestions were focused on travelers who spend their road time behind the wheel and can either save money or maximize the return on what they do spend.

At the gas pump, Kerr suggests using a card that offers bonus points on fill-ups. For example, the Hilton Honors American Express Ascend Card offers 6x points per dollar spent at US gas stations, while several Citi cards - like the Citi Premier Card - offer bonuses. By using the Hilton card, you can quickly earn enough points for free hotel nights, whether at budget properties or luxury resorts.

However, even though "[some] of the Citi cards have really great deals," Kerr suggests that beginners focus on earning Chase and AmEx points.

That's because Chase and AmEx points make it easier to get outsized value. Having an anchor card with comprehensive benefits - like the Chase Sapphire Reserve or the Platinum Card® from American Express - can be a great first step. That's even more beneficial for military servicemembers on active duty, since they can get the annual fee waived on those premium cards.

The next step would be to use a companion card that will earn the highest amount possible on gas.

For example, some cards from Chase, like the Chase Freedom Unlimited, which is marketed as earning 1.5% cash back, actually earns 1.5x points per dollar, which can be pooled with points earned from other Chase cards - including the Sapphire Reserve.

Something big that's worth noting if you're planning to rent a car: Both the Chase Sapphire Reserve and the AmEx Platinum offer car rental benefits, including discounts and elite status with agencies like Avis, National, Enterprise, and Hertz.

However, the Sapphire Reserve has a major advantage over the Platinum Card when it comes to car rentals. In addition to benefits at rental agencies, it offers primary rental car collision/loss insurance, as long as you pay with the card and decline the collision damage waiver coverage offered by the rental agency. You may still want to consider liability insurance if you aren't otherwise covered, but the rental collision/loss coverage from the card can save you a ton.

Kerr also suggests linking cards to programs like the Fuel Rewards program at Shell. Between the savings Fuel Rewards offers on fill-ups - especially because you can earn Fuel Rewards discounts at other retailers besides Shell - and the points you can earn from credit card rewards on fuel, benefits can add up quickly.

"Yesterday, I filled up 20 gallons of gas for a net total of about $0.38," he said.

He recommends signing up for Fuel Rewards, which is running a partnership in conjunction with Award Travel 101 - you'll get Gold status right away, and immediately start saving $0.05 per gallon.

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Business Insider may receive a commission from The Points Guy Affiliate Network, but our reporting and recommendations are always independent and objective.