What Is Miles Per Dollar (mpd)? A Plain Guide

Every miles credit card leads with the same number: "earn up to X miles per dollar." That figure is miles per dollar, or mpd, and it's the most quoted stat in the whole game. The trouble is that the headline rate rarely tells you what you'll actually earn. Here's how to read it without being misled. If you're new to all this, start with how air miles work and come back.

What mpd means

Miles per dollar is what it sounds like: how many miles you earn for each dollar you spend. A card earning one mile per dollar gives you one mile for every dollar. A card earning two miles per dollar earns twice as fast on the same spending. That part is easy. The complications all come from which spending earns which rate, and that's where most people trip up.

The reason the number matters is compounding over a year of normal spending. A small gap in the rate looks trivial on a single coffee, but run a year of groceries, bills and the odd holiday through the card and the difference between a low rate and a high one adds up to a meaningful pile of miles, or a meaningful pile you never earned. That's why the rate gets so much attention. It's also why the marketing leans so hard on the biggest number it can find.

Why local and foreign spend earn differently

Almost every Singapore miles card has at least two rates. There's a base rate for everyday local spend, and a higher rate for foreign-currency spend, online spend, or specific categories such as dining. Why the gap? Banks earn more on cross-border and category transactions, so they hand some of it back to you as bonus miles. The practical upshot: that "up to" number usually applies to one slice of your spending, not the lot.

So when you see a headline rate, the first question to ask is what triggers it. Some cards reserve the top rate for spending in a foreign currency, which means a local online order billed in Singapore dollars earns the lower rate even though you bought it online. Others tie the bonus to a named list of merchants or categories, and anything off that list drops back to base. The wording in the terms is doing real work here, and two cards quoting the same "up to" figure can pay out very differently once you map the rate to where your money actually goes.

The catches that shrink your mpd

A few things quietly pull your real earn rate below the headline.

Bonus rates often unlock only after you hit a monthly minimum spend, so a quiet month can drop you to the base rate without warning. Many cards then pay the bonus rate only up to a monthly cap, and once you cross it the extra spend earns the base rate again. On top of that, whole categories get excluded. Insurance, education, government payments and utilities frequently earn nothing at all, so it's worth reading the exclusion list before you assume a big bill will earn.

There's also rounding to watch. Some cards round your spend down to the nearest dollar before they award miles, so a long tail of small odd-cent purchases can leak a bit of earn that never shows up. And the way miles post can hide the real picture too: a card might split a transaction into base miles and bonus miles credited at different times, which makes it easy to glance at your statement and assume you earned less than you did, or more.

Put those together and the mpd you actually pocket sits somewhere below the one printed on the marketing page. The headline rate is the ceiling, not the floor. Your job when reading it is to work out how far below that ceiling your own spending will land.

mpd isn't the whole story

A high earn rate is worthless if you redeem the miles badly. A card that earns fewer miles you redeem brilliantly will beat one that earns more miles you let rot (why redemption matters). And a high foreign mpd comes with a foreign transaction fee, so net the extra miles against that cost instead of treating foreign spend as a free win. Sometimes it is. Sometimes the fee quietly cancels out the bonus.

How to use mpd when choosing a card

Match the card's bonus categories to where your money actually goes. A great dining rate does nothing for you if you rarely eat out, and a generous online rate is wasted if most of your spend is in person. Check the minimum spend and the cap next, because those two numbers tell you the rate you'll realistically hit rather than the one on the poster. Then weigh all of that against the annual fee, and against how good you are at redeeming what you earn.

A quick way to sanity-check a card is to picture a normal month of your own spending and ask which parts would actually earn the bonus rate. Strip out the bills that get excluded, the spend that sits in the wrong category, and anything beyond the monthly cap. What's left is the slice earning the headline number, and the rest earns base. Run that rough sum in your head and the "blended" rate you'll really get usually looks a lot more modest than the poster, which is exactly the figure you want to compare cards on.

If your spending is lumpy or spread across categories, two cards can also make sense at once, with each handling the spend it pays best on. That's a more advanced move and not worth it for everyone, but it's the logical end of matching the rate to the spend rather than forcing all your spend onto one rate that only suits part of it.

The takeaway

mpd tells you how fast you earn, not how much your miles are worth. Read past the "up to" headline to the base rate, the caps and the exclusions. A high earn rate only pays off if you redeem well and don't hand the gains straight back in fees.