diff --git a/docs/departures.md b/docs/departures.md
index 038b9edf..e92583a7 100644
--- a/docs/departures.md
+++ b/docs/departures.md
@@ -26,6 +26,7 @@ With `opt`, you can override the default options, which look like this:
 	// todo: products
 	when:      new Date(),
 	direction: null, // only show departures heading to this station
+	line: null, // filter by line ID
 	duration:  10, // show departures for the next n minutes
 	results: null, // max. number of results; `null` means "whatever HAFAS wants"
 	subStops: true, // parse & expose sub-stops of stations?
diff --git a/format/station-board-req.js b/format/station-board-req.js
index b81918ea..f29ab01c 100644
--- a/format/station-board-req.js
+++ b/format/station-board-req.js
@@ -3,15 +3,20 @@
 const formatStationBoardReq = (ctx, station, type) => {
 	const {profile, opt} = ctx
 
+	const jnyFltrL = [
+		profile.formatProductsFilter(ctx, opt.products || {})
+	]
+	if (opt.line !== null) {
+		jnyFltrL.push({type: 'LINEID', mode: 'INC', value: opt.line})
+	}
+
 	const req = {
 		type,
 		date: profile.formatDate(profile, opt.when),
 		time: profile.formatTime(profile, opt.when),
 		stbLoc: station,
 		dirLoc: opt.direction ? profile.formatStation(opt.direction) : null,
-		jnyFltrL: [
-			profile.formatProductsFilter(ctx, opt.products || {})
-		],
+		jnyFltrL,
 		dur: opt.duration
 	}
 	if (opt.results !== null) {
diff --git a/index.js b/index.js
index f41c769b..b3c3bf12 100644
--- a/index.js
+++ b/index.js
@@ -56,6 +56,7 @@ const createClient = (profile, userAgent, opt = {}) => {
 		opt = Object.assign({
 			// todo: for arrivals(), this is actually a station it *has already* stopped by
 			direction: null, // only show departures stopping by this station
+			line: null, // filter by line ID
 			duration: 10, // show departures for the next n minutes
 			results: null, // max. number of results; `null` means "whatever HAFAS wants"
 			subStops: true, // parse & expose sub-stops of stations?