How the Leave-By Calculator Works

If you've accumulated miles or hotel points across multiple programs, you've probably experienced the quiet anxiety of wondering: are any of these expiring?The Leave-By Calculator is designed to answer that question clearly, without requiring you to track down and parse each program's fine print.

The Problem It Solves

Loyalty program expiration policies are inconsistent, frequently updated, and easy to misread. Some programs expire points after a fixed date from account opening. Others expire after a period of inactivity — typically 12–24 months without an earning or redemption transaction. Some have no expiration at all. A few use tiered rules where elite status members have different windows than base members.

The result: travelers often don't realize points are close to expiring until it's too late to use them well. They either rush into a low-value redemption to preserve the balance, or lose the points entirely.

The Leave-By Calculator addresses this by:

1. Showing you the expiration deadline for your current balance (where the program has a defined rule)
2. Showing you the minimum activity needed to extend that deadline
3. Surfacing what redemption options are currently available within your expiration window

How the Deterministic Model Works

“Deterministic” means the calculator's outputs are mechanical, not probabilistic. Given your current balance, your account's last activity date, and the program's published rules, the expiration date is a fixed calculation — not an estimate or a recommendation.

The calculator uses three inputs:

• Program rules — expiration policy type (activity-based vs. fixed), which activity types qualify, the extension period granted per activity
• Your last activity date — the most recent qualifying earn or redemption transaction
• Current balance

It then produces:

• Expiration date — the exact date the current balance expires if no qualifying activity occurs
• Days remaining — calendar days until expiration from today
• Extension path — the lowest-friction activity that would reset the clock (e.g., a small card purchase, a partner transfer, a hotel stay)

No inference, no probability scoring — it's arithmetic on published policy data.

What “Leave By” Means Specifically

The “leave-by” date refers to the date you'd need to initiate a qualifying redemption or activity to ensure your points don't expire before you can use them.

This is distinct from the expiration date itself. If your points expire in 90 days, but a specific award booking requires 30 days of advance purchase lead time and your preferred dates need to be reserved now, your functional leave-by date for that opportunity is earlier than the expiration date.

The calculator surfaces available opportunities in the context of your remaining window, so you can see what's practically reachable — not just whether the balance will technically survive.

Example: Activity-Based Expiration

Suppose your United MileagePlus account shows:

• Last qualifying activity: 14 months ago
• Program rule: points expire after 18 months of inactivity
• Your expiration date: 4 months from today

The Leave-By Calculator would show:

• Expiration date and days remaining
• That a qualifying activity (e.g., a MileagePlus card purchase, a United flight, a partner hotel stay) would reset the 18-month clock
• Awards currently available for the balance, filtered to bookings feasible within a 4-month window

In this scenario, a small purchase on a co-branded card before the expiration window closes would extend your options significantly.

Note: Program rules are illustrative. Verify qualifying activity types with the program directly.

Program Coverage and Limitations

The Leave-By Calculator covers the programs listed in the app. Coverage expands as program rules are verified and integrated.

Important limitations to know:

Policy changes. Airlines and hotels update their expiration policies without advance notice. We update program rules as changes are confirmed, but there may be a lag between a program change and the calculator reflecting it. Always verify the current policy with the program before making decisions based solely on the calculator output.

Activity eligibility.Not all activities reset the expiration clock. A credit card purchase on a co-branded airline card typically counts; incidental purchases through non-participating partners may not. The calculator applies the program's stated qualifying activity types as published — always confirm with the program if you're unsure whether a specific activity qualifies.

Co-branded card differences. Some programs grant extended expiration windows to co-branded cardholders. The calculator applies standard program rules unless a cardholder-specific policy is explicitly documented; cardholders may have additional options not reflected in the default view.

Balance size doesn't change the deadline. For activity-based programs, the expiration date applies to your entire balance, not just the portion you want to preserve. The Leave-By Calculator treats the full balance as a single unit.

Why This Feature Exists

Most award tools are designed to help you find and book awards — they're search-first. The Leave-By Calculator addresses a different, earlier question: given what you already have, when does it need to be used?

Simpli's view is that good redemption decisions require clarity on the full picture: what you have, what it's worth, when it expires, and what's available within your window. The Leave-By Calculator is one piece of that picture; the comparison view handles the value side.

How to Use It

Navigate to the Leave-By Calculator. Enter your program, current balance, and last activity date. The calculator displays your expiration timeline and surfaces opportunities within your window.

From there, you can cross-reference against the comparison view to evaluate the CPP of any opportunities that surface — connecting the timing question (when do I need to act?) with the value question (is this redemption worth it?).

For the value side of the decision, see Cash vs. Points: When Should You Pay Cash vs. Use Miles? and What Is Cents Per Point (CPP)?