What a roll is
Rolling out: close this expiry, open a later one (same strike or adjusted). Rolling up/down: change strike. A diagonal roll changes both. On venues with combo orders you may get a single net price; otherwise you are two-legged and can get legged.
People roll to “avoid taking a loss.” That often just postpones theta and adds fees. Only roll if the view still deserves capital at the new marks.
Price both sides
Mark the position you close (bid if you are selling it back, etc.) and the position you open. The difference is the roll debit or credit before fees. If you are rolling a losing long call to a later ATM, you may be paying a large debit to buy more time — that is a new long-vol purchase.
Use /t/{asset}/chain on both expiries. Term desk shows whether you are rolling into richer or cheaper IV.
Combos versus legging
Multi-leg / combo execution reduces leg risk when the venue supports it. If not, use limits and accept that one leg may fill. Market-rolling illiquid wings is how you donate the edge you were protecting.
See multi-leg-execution and limit-vs-market.
When rolling is the wrong move
The event already happened. IV crushed and you are manufacturing a new trade to avoid a journal entry. The next book is empty. Geo/product access changed. Margin on the new short is larger than your rule.
Closing is a valid outcome. OptionsMatch trade-idea logs on the account hub are for journaling — they do not require you to keep a position alive.
Hedges and shorts
Rolling a protective put: you are buying a new insurance policy. Compare cost to just selling inventory. Rolling a short: you may be chasing a credit into a worse skew. Re-underwrite max loss.
Calendar structures are intentional rolls in one package — different from emergency rolling a naked short.
Practice this on OptionsMatch
Compare two expiries on /t/btc/chain and /t/btc/term. Simulate the new shape in /t/btc/strategy. Execute the roll on the venue as a combo if you can.
Educational only.