diff --git a/docs/src/reference-main-then-chaining.md.in b/docs/src/reference-main-then-chaining.md.in
index 293124aa2..1f8cd81c7 100644
--- a/docs/src/reference-main-then-chaining.md.in
+++ b/docs/src/reference-main-then-chaining.md.in
@@ -21,3 +21,5 @@ GENMD-INCLUDE-ESCAPED(data/then-chaining-performance.txt)
 There are two reasons to use then-chaining: one is for performance, although I don't expect this to be a win in all cases.  Using then-chaining avoids redundant string-parsing and string-formatting at each pipeline step: instead input records are parsed once, they are fed through each pipeline stage in memory, and then output records are formatted once.
 
 The other reason to use then-chaining is for simplicity: you don't have re-type formatting flags (e.g. `--csv --fs tab`) at every pipeline stage.
+
+As of Miller 6.3.0, `+` is an alias for `then`.
diff --git a/internal/pkg/climain/mlrcli_parse.go b/internal/pkg/climain/mlrcli_parse.go
index df24b2c64..2ae365968 100644
--- a/internal/pkg/climain/mlrcli_parse.go
+++ b/internal/pkg/climain/mlrcli_parse.go
@@ -162,10 +162,10 @@ func parseCommandLinePassOne(
 				os.Exit(1)
 			}
 
-		} else if onFirst || args[argi] == "then" {
+		} else if onFirst || args[argi] == "then" || args[argi] == "+" {
 			// The first verb in the then-chain can *optionally* be preceded by
 			// 'then'.  The others one *must* be.
-			if args[argi] == "then" {
+			if args[argi] == "then" || args[argi] == "+" {
 				cli.CheckArgCount(args, argi, argc, 1)
 				oargi++
 				argi++