Field Notes

Notes on running a wallet of premium cards.

Strategy, timing, and the math nobody else shows you. Every piece here is built on the same honest-math principle the rest of CARDIER is built on: substantiated numbers, named card mechanics, no fabricated averages.

Latest
Education

Planning a Platinum Credit Calendar for 2026

The Amex Platinum advertises a large annual credit stack. What it does not advertise is that those credits run on three different clocks. Here is how to lay them out so you actually catch every one.

8 min readJuly 4, 2026
Read piece
Strategy

The Real Cost of Credit Card Annual Fees: Should You Keep Your Cards?

A $695 annual fee is not a price — it is a wager. Here is how to calculate, card by card, whether your premium cards are actually paying you back.

9 min readJuly 2, 2026
Education

Why So Many Credit Card Benefits Quietly Expire Unused

Statement credits do not vanish because cardholders are careless. They vanish because the reset calendars are deliberately incoherent. Here is how the timing actually works.

7 min readJune 25, 2026
Strategy

CARDIER vs. a Spreadsheet: What Actually Gets Tracked

The honest competitor to CARDIER is not another app. It is the spreadsheet the diligent cardholder has already built. Here is where the spreadsheet quietly stops working, and why.

7 min readJune 18, 2026
Optimization

Sign-Up Bonuses: How the Minimum Spend Math Actually Works

A welcome bonus is a contract — points in exchange for a specific dollar amount of spend in a specific window. The framework for hitting it without buying things you do not need.

6 min readJune 11, 2026
Strategy

Credit Card Portfolio Strategy: Building a Wallet That Holds Together

Most premium cardholders have too many cards. Not too few. Here is a framework for building a small, intentional wallet — and the overlap traps to avoid when you add a card.

8 min readMay 28, 2026
Trust

Why Cardier Doesn’t Ask For Your Bank Login

A credit-card benefit tracker does not need access to your bank account to do its job. Here is why we made that the default — and what the design tradeoff is.

5 min readMay 14, 2026