Time-in-force (GTC, IOC, FOK, post-only)

Time-in-force (TIF) decides what happens to a limit order that can’t fill completely the moment it arrives: rest in the book, fill what it can and cancel, fill entirely or die, or refuse to take liquidity at all. Nocterm supports the four standard modes on paper, on the Replay sim, and - where the venue supports them - live.

Where: trade ticket ▸ TIF row · DOM ▸ Post chip · chart options ▸ Time in Force · bot scripts ▸ tif=Default: GTC

The trade ticket's TIF row with GTC / IOC / FOK / POST

The four modes

Mode	On arrival	If it can’t fill completely
GTC (good till cancelled)	Fills what’s marketable, rests the rest	Keeps working until filled or cancelled
IOC (immediate or cancel)	Fills whatever the visible book serves inside your limit	Cancels the remainder - a partial fill is kept, the order ends Cancelled
FOK (fill or kill)	Checks the visible depth inside your limit first	Rejected whole - it never rests and never partially fills
POST (post-only)	Rejected if it would cross the book	Rests as a maker order; it can never take liquidity

TIF is a limit-order concept. Market orders always execute immediately, so the setting doesn’t apply to them. Stop-limit orders honor their TIF at the moment the trigger converts them into a limit - a post-only stop-limit that would cross at its trigger is cancelled instead of taking.

Why you’d use each

• GTC is the everyday default - place it and let it work.
• IOC takes the liquidity that’s there right now without leaving a resting order behind - useful when you want size immediately but refuse to sit in the book.
• FOK is all-or-nothing: either your full size is available inside your price or nothing happens. No partial position to manage.
• POST guarantees the maker fee rate. If your limit would execute immediately (taking), it’s rejected instead, so a filled post-only order always paid maker, never taker. A resting post-only order also refuses to be amended onto a crossing price. See trading costs for how maker and taker rates differ.

Where to set it

• Trade ticket - a GTC / IOC / FOK / POST row appears when the order type is Limit. The choice persists with the ticket.
• DOM ladder - the Post chip makes every ladder-click limit entry post-only (market buttons are unaffected).
• Chart right-click orders - the chart options panel has a Time in Force section; the right-click Long/Short entries use it and show a non-default choice inline, e.g. Long 0.01 @ 42000 (POST).
• Bot scripts - pass tif = "gtc" | "ioc" | "fok" | "post" in bot.buy{...} / bot.sell{...}. An unknown value errors the action rather than silently defaulting.

Live-venue support

Live venues only get the modes they actually implement - anything else is rejected up front with a clear toast rather than silently downgraded:

Venue	GTC	IOC	FOK	Post-only
Paper / Replay	✓	✓	✓	✓
Kraken spot	✓	✓	-	✓
Kraken futures	✓	✓	-	✓
Alpaca	✓	✓	✓	-

Tip

An IOC that partially fills shows as Cancelled with a filled quantity in the blotter - that’s the standard exchange convention, not an error. The filled slice opened a position; the cancel is just the unfilled remainder.

Related

• The trade ticket - where the TIF row lives.
• Trading costs - maker vs taker fees, which post-only guarantees.
• Order rejections - the TIF rejection messages.