Selling a cash-secured put is the easy part. You pick a strike, you collect a premium, and you wait. The part that trips most option sellers up is everything that happens after that — the rolls, the partial closures, the eventual assignment, and the running tally of how much premium has actually reduced your real cost basis in the underlying stock.
Spreadsheets can handle one or two positions. They start falling over once you have a ticker you've rolled four or five times, because you need to remember which contracts closed which positions, which premiums are tied to which rolls, and what your actual breakeven price is if and when you finally get assigned.
This walkthrough shows a full TSLA example — selling an initial cash-secured put, rolling it twice as the stock climbs, getting assigned when it finally expires in the money, and watching the True Cost Basis update at every step so you always know the real number.
The demo starts with a brand-new Tesla portfolio — no positions, no transactions, no history. The goal is to watch every row and every number populate in real time as the position moves through its life cycle.
TSLA is trading around $400 a share, which means a single cash-secured put contract requires roughly $40,000 in collateral. The demo funds the account with a $150,000 deposit so there's plenty of room for the position plus a comfortable buffer.
Ticker: TSLA
Deposit: $150,000
Current price: ~$400
Strategy: Sell weekly cash-secured puts and track what happens
With the capital in place, the first stop is the Cost Basis v2 tab, where all ticker-level positions live. TSLA gets added as a new symbol, and the running totals — shares owned, collateral on the table, cost basis metrics, realized gains — all start at zero.
The first transaction is a standard sell-to-open put at the $375 strike, expiring the following Friday. The premium received is $2.85 per share, which works out to $285 on a single contract — a return of about 0.76% on the collateral for the week.
Inside MyATMM, the new put gets entered on the puts tab of the ticker detail page. The form captures the essentials every option seller needs to track:
Commissions and fees pre-fill from the account-level defaults, and a proposed transaction preview shows up at the bottom of the form before you commit. Once you save, two things happen simultaneously: the put appears as an open position on the ticker, and a corresponding transaction is written to the ledger. No duplicate entry, no manually reconciling two different records.
The first put doesn't get tested. TSLA climbs instead of falling, and by Friday the $375 strike is well out of the money. Rather than wait for Monday to sell a new one, the trader rolls the position into the following week — but with a higher strike, because the stock has moved up and premiums are better closer to the money.
In MyATMM, rolling is a single action. From the existing put position, clicking Edit reveals a Roll link. The roll form asks for:
In the demo, the roll goes from the $375 strike to the $385 strike, with a $3.15 premium. The proposed transaction preview is specific about what's about to happen: the old $375 put position will be deleted, a new $385 put position will be created, and a single transaction will be written to the ledger capturing the new sell-to-open.
The same process repeats a week later. TSLA keeps grinding higher, so the $385 put rolls into a $405 strike at $4.25 premium for a third week. Every roll adds to the stacked premium total, and every roll keeps the position count clean: at any given moment there's only one open put on TSLA, but the transaction log has every premium you ever collected against the ticker.
On the third week, the trade catches up. TSLA closes at $400 on expiration Friday with the put struck at $405 — officially in the money. An in-the-money put will be assigned over the weekend, which means the trader wakes up Monday owning 100 shares at $405 apiece.
Logging the assignment in MyATMM mirrors the roll flow. From the open put position, clicking Edit now shows an Assigned option. The form pre-fills the obvious fields: the assignment date is typically the Monday after expiration, the transaction type is a buy-to-open (you're buying the stock), the contract count translates into shares (one contract = 100 shares), and the assignment price is the strike.
Date: Monday after expiration
Action: Buy to open 100 shares
Price: $405.00 (the strike)
Total cost: $40,500
Commissions/fees: Usually $0 on assignments (broker-dependent)
Confirming the assignment triggers the same kind of clean-up a roll does: the open put position disappears, 100 shares of TSLA appear on the stock tab, and a new buy transaction lands on the ledger. The ticker header at the top of the page updates to show 100 shares held, and a small warning icon appears to flag that the new shares aren't yet covered by a covered call — a gentle nudge that a covered call is a natural next move if you're running the wheel.
This is where the tracking pays off. You just bought 100 shares of TSLA at $405 while the market is at $400. On the surface, that looks like a 100-share position underwater by $500.
But that's not your real cost. You collected $285 on the first put, $315 on the first roll, and $425 on the second roll — $1,025 in total premium on this ticker before you ever owned a share. Your actual breakeven on the stock isn't $405. It's $405 minus $10.25 per share in collected premium, or roughly $394.75.
The ticker header in MyATMM exposes this directly. Several different cost basis numbers are displayed side by side, each with a specific meaning:
| Metric | What it means |
|---|---|
| Cost basis | The straight cost of the shares you own ($405 × 100 = $40,500) |
| Cost basis with puts | Speculative basis if any open cash-secured puts were assigned |
| Cost basis minus premium | Your basis if you want to retain every penny of premium you collected ($405 − premiums) |
| True cost basis | Cost minus premiums and dividends collected — your real breakeven to exit flat |
This is the kind of nuance that makes brokerage statements feel incomplete. Brokers show you what you paid for the shares. MyATMM shows you what those shares actually cost you once every premium and every dividend collected on the ticker is accounted for.
Everything above happens on the ticker-detail page, but the dashboard is where the portfolio-wide view lives. A few tabs worth a closer look:
Breaks down every week's total premium and dividend collection across every ticker you track. Small columns for quiet weeks, taller ones for the weeks you rolled a meaty position. Great for spotting cadence and figuring out which weeks you want to load up on new positions.
A snapshot of everything you currently hold — open options, owned stock, and the collateral tied up behind each one. After the TSLA assignment, the 100 shares show up here alongside any other positions you're tracking.
Filter the ledger down to just premium events. Useful if you want to review nothing but what you've collected on options, or if you want to see your dividend stream in isolation.
The most useful tab for traders targeting a weekly or monthly return. Each row is a period — deposits, withdrawals, premiums collected, dividends collected, realized gains and losses — plus your net working capital at the end of that period. The percentage column tells you what your premium/dividend collection represents against your total working capital, and the annualized view projects that forward so you can see whether you're on pace for your goals.
The reason spreadsheets buckle under active options selling is that every roll, every partial close, every assignment creates a small cascade of changes: the old position has to be closed, a new position has to be created, a new transaction has to be logged, and every cost basis number has to be recalculated against every premium you've ever collected.
MyATMM is purpose-built to handle that cascade without the user having to think about it:
And because every transaction is tagged, filtered, and tied to the position that created it, there's an audit trail you can scroll through any time you want to reconstruct why a cost basis number looks the way it does.
Options trading involves risk and is not suitable for all investors. Past performance does not guarantee future results. Getting assigned on a cash-secured put means you're committed to buying 100 shares at the strike price, even if the stock has fallen well below that level. This content is for educational purposes only and should not be considered financial advice. Always consult with a qualified financial advisor before making investment decisions.
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