Budget + optimization · in private beta

What's your wallet leaving on the table?

Stack is a budget app that pays you back. Track every dollar coming in. Maximize every dollar going out. Both halves of your money, one app.

Joining the waitlist is free and gets you the first invitations. It does not hold a slot. No credit card required.

Max · just now
$87 dinner at Carbone. Which card?
USE THE
Amex Gold.
4× Membership Rewards. 348 pts.
Why this over Sapphire? ›
Spend caps · 3 active
Amex Gold · US Supermarkets
$24,200 / $25,000
~2 weeks until cap. Drops 4× to 1×.
Citi Custom Cash · Restaurants
$420 / $500
$80 left at 5% this month.
Freedom Flex · Rotating 5%
$890 / $1,500
~6 weeks of headroom.

They've turned your wallet into a game, and it's tired you out.

Every one of these is a daily problem you've probably experienced for years. Stack is the budget app built around solving them.

i.
Standing at the register, blank.
Sapphire Preferred for dining, but is this dining? Is the Amex Gold's cap maxed? You picked one, swiped, and immediately doubted yourself. Stack answers in one tap, before you tap.
ii.
The spreadsheet that became a chore.
It started as a clever Notion page. Quarterly categories, 5/24, statement credits, sign‑up bonus thresholds. Now updating it costs more time than the rewards it tracks. Spreadsheet refugees: this was built for you.
iii.
Your Amex airline credit expired Tuesday.
$200 left behind because nothing reminded you. The dining credit, the hotel benefits, the last minute concert tickets you almost forgot to book. Stack tracks every statement credit and gives you a friendly reminder to use it.
iv.
NerdWallet works for whoever pays them.
"Best card for groceries" is the card with the biggest affiliate payout to NerdWallet. You know this. You've stopped trusting them. We don't weight recommendations by affiliate payout. Ever. (See the pledge below.)

Two questions you're tired of answering. Stack answers them for you.

Most apps focus on your household budget or optimizing your wallet. Stack believes in optimizing the entire budget. Every dollar should be put to work. Especially the expenses.

i.
Which card right now?

Ask Max.

Max is your in-app wallet assistant that helps you find the right card, at the right time. "Which card should I use for dinner?" Max answers with one card. "Use the Amex Gold." That's it. Max will explain the points math, cap headroom, second-best alternative, and the merchant category code if you want it. All there. All hidden until you tap.

Built for the person who wants the answer. And the partner who just wants the swipe to be right.

One‑tap answer Real bank data No bank link required Manual cards work too
Max · live data
$87 dinner at Carbone. Which card?
USE THE
Amex Gold.
4× Membership Rewards. 348 pts earned.
Why this over Sapphire Reserve? ›
ii.
When does my bonus run out?

The Cap Tracker.

Every category bonus you have, tracked in real time. Amex Gold burning through the $25k Grocery cap? Custom Cash 5% category maxed out for the month? Freedom Flex still has $1k in spending space for the quarter? Stack does the math. You see the bar. The moment you're closing in on the cap, we'll be there to tell you.

Live progress bars Estimated cap‑hit dates Per‑card configuration Statement credit reminders
Spend caps · live
Amex Gold · US Supermarkets
$24,200 / $25,000
~2 weeks until cap. Drops 4× to 1× at the line.
Citi Custom Cash · Restaurants
$420 / $500
$80 left at 5% this month, then 1×.
Freedom Flex · Rotating 5%
$890 / $1,500
~6 weeks of headroom. Plenty.

Mint died. The replacements forgot the rewards.

Mint shut down in March 2024. 3.6 million people went looking. The replacements raised over a hundred million between them to build a better budget tracker. Nobody bothered to ask which card. Stack is the budget app built for the half of the wallet they ignored.

App
Capital Raised
What it does
Mint
~$170M acq · $0 sunset
Free model. Couldn't sustain. Sunset March 2024.
Monarch
$94.8M raised
Beautiful budgeting. Doesn't touch credit‑card rewards.
Copilot
$11.1M raised
Prettiest budget app on iOS. Card‑blind.
MaxRewards
$4M raised
Card optimization. No budget tracking.
CardPointers
Bootstrap
No bank link required. Manual everything. Loved on r/CreditCards.
Stack
2026
Both halves of your money. Real data. Honest recommendations.

They raised more and built half the wallet. Stack is built for both halves.

An honest commitment

The recommendation is personal, not paid.

Most rewards apps recommend the card with the biggest affiliate payout. We won't. Stack's recommendations come from your spending, your existing wallet, and your situation. The bank paying us nothing and the bank paying us the most get the same fair shot at the recommendation.

Here's how the money actually works. We're building an Explore Cards feature where you can apply for new cards through Stack. If you choose to apply, the issuing bank may pay us a referral. That's the only time affiliate revenue enters Stack's books. Not at the recommendation step. Not in Max's answers. Only when you decide to apply.

The line we'll never cross: a recommendation is never weighted by what we'd earn. The card recommended to you is the card that's right for you. Always. If we ever break this, hold us to it.

S
Founder, Stack App

Pay once a year. Lock it for life.

Founding pricing opens with the beta. Join the waitlist for first access. The first 1,000 paid members get Stack Pro at $89.99 a year, locked for life. The first 250 can take Lifetime at $249 once. The public price after the Founding cap is $99.99 a year.

Free · forever
$0
A real tool, not a paywall preview. Genuinely useful, free forever.
  • Manual cards
  • Max. Which card right now
  • 40 Max queries per month
  • Missed Rewards, single month (manual data)
  • Manual Budget Tools
  • Goal Management
  • Manual Benefits Tracker
Start free
Lifetime
Pro · one-time
$249 once
Pay once, never again. Hard cap of 250, ever.
  • Everything in Founding Member
  • One-time payment. No subscription
  • Lifetime Founder badge (distinct)
  • Future Pro features included, forever
Join the waitlist

Prefer monthly? $9.99/mo, same Pro features. Monthly is billed when you start, no trial. The 30-day free trial is on Pro Annual. Join the waitlist ›

30-day free trial on Pro Annual
Try every Pro feature free for 30 days, then $99.99 a year. Cancel during the trial and pay nothing.
Founding and Lifetime are paid up front
No trial, because the locked price and the slot are the point. A 7-day full refund covers you if you change your mind.
7-day refund, one click
Charged and changed your mind within 7 days? Full refund in Settings, no ticket, no friction.

FAQ.

How does Stack show me what I'm leaving on the table?
Once Stack has your transactions, whether you enter them by hand or link a bank, and the cards in your wallet, we compare what you actually earned on each purchase against the highest-value card you could have used. The gap, across every transaction, is what we call your Missed Rewards. Your number depends entirely on your spend and your cards, so we show you yours, not a marketing average. On Free you see a single month from transactions you enter by hand. On Pro, Stack pulls it in automatically and tracks it every month.
Do I have to link my bank?
No. Stack works with cards you add by hand, and Max, the budget, and Cap Tracker all run on manual data with no bank link. Missed Rewards is the one feature that needs your transaction history, and there are two ways to feed it. On Free, enter a month of transactions by hand and see your number. On Pro, link your bank through Plaid and Stack tracks it automatically, every month. The bank link is the convenience upgrade, not the gate.
What about my data?
Bank-grade encryption. Never sold, never shared. If you do choose to link a bank, Plaid handles that connection. Same plumbing Venmo, Robinhood, and Coinbase use. Read the privacy policy for the full version.
Why $89.99 a year?
Honest answer, we are new, and we are competing on permanence, not on a sale. Founding Member pricing locks $89.99 a year for the first 1,000 paid signups, with no annual increases, ever. After the cap fills, the public price moves to $99.99 to sit in line with the category. Plenty of apps discount below their list price, then raise it again. Your Founding Member price is contractually locked the day you sign up.
What's the difference between Founding Member and Lifetime?
Founding Member is annual at $89.99/yr, locked for life for the first 1,000 paid signups. As long as your subscription stays active, that price never changes. No annual increases, ever. Lifetime is $249 one-time for the first 250 paid signups. After 250, the tier closes permanently. Lifetime users never pay again, including for future Pro features. Both come with a 7-day refund window, one click, no support friction. The Lifetime price is contractually guaranteed forever, not dependent on a sale we might end tomorrow.
Is there a free trial? What happens on day 30?
The 30-day free trial is on Pro Annual. Try every feature free for 30 days, then it renews at $99.99 a year unless you cancel. Founding Member and Lifetime work differently: you pay up front to lock the price and claim the slot, with a 7-day full refund if you change your mind.
When does Stack open up?
Currently in private beta with a small group of power users. Full launch planned for 2026. Join the waitlist to stay up to date and take advantage of Founder pricing.
Does joining the waitlist guarantee a Lifetime or Founding Member spot?
No. Joining the waitlist is free and gets you the first invitations when pricing opens. Slots are claimed at paid signup, not at waitlist join, so the earlier you convert the better your odds. Lifetime in particular is hard-capped at 250, ever, with no reopening.
Wait, do you take affiliate money?
Yes, but only at one specific moment. When the Explore Cards feature ships, you'll be able to apply for cards through Stack. If you choose to apply, the issuing bank may pay us a referral. That's the only time affiliate revenue enters our books. Recommendations themselves, anywhere in the app, are based on your data, never on who pays us more. We've made that line public so we can be held to it. Read the pledge above.

Join the list for your chance at Founding/Lifetime Member pricing.

Joining the waitlist is free and gets you the first invitations. It does not hold a slot. No credit card required.

Made for spreadsheet refugees. Built honestly.
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