diff --git a/internal/templater/funcs.go b/internal/templater/funcs.go
index 7622a53c..5d8b7d1a 100644
--- a/internal/templater/funcs.go
+++ b/internal/templater/funcs.go
@@ -63,7 +63,7 @@ var legacySprigAliases = sprout.FunctionAliasMap{
 
 func init() {
 	handler := sprout.New(
-		sprout.WithLogger(slog.New(slog.DiscardHandler)),
+		sprout.WithLogger(slog.New(noticeHandler{})),
 		sprout.WithRegistries(
 			taskfuncs.NewRegistry(),
 			backward.NewRegistry(),
diff --git a/internal/templater/notices.go b/internal/templater/notices.go
new file mode 100644
index 00000000..5f03baf9
--- /dev/null
+++ b/internal/templater/notices.go
@@ -0,0 +1,57 @@
+package templater
+
+import (
+	"context"
+	"log/slog"
+	"sync"
+	"sync/atomic"
+)
+
+// NoticeFunc receives the deprecation notices that sprout emits when a
+// template calls a deprecated function name or uses a deprecated argument
+// order.
+type NoticeFunc func(format string, args ...any)
+
+// noticeSink is set once the Executor has built its logger. Until then — and
+// the function map is built in an init(), long before that — notices are
+// dropped rather than written to sprout's default stdout handler, which would
+// corrupt the JSON and group output styles.
+var noticeSink atomic.Pointer[NoticeFunc]
+
+// SetNoticeSink installs the destination for template deprecation notices.
+// Passing nil silences them again.
+func SetNoticeSink(fn NoticeFunc) {
+	noticeSeen.Clear()
+	if fn == nil {
+		noticeSink.Store(nil)
+		return
+	}
+	noticeSink.Store(&fn)
+}
+
+type noticeHandler struct{}
+
+func (noticeHandler) Enabled(_ context.Context, level slog.Level) bool {
+	return level >= slog.LevelWarn && noticeSink.Load() != nil
+}
+
+// noticeSeen keeps each distinct notice to a single line. Task renders the
+// same templates several times per run — once per compilation pass — so
+// without this a lone deprecated call would be reported over and over.
+var noticeSeen sync.Map
+
+func (noticeHandler) Handle(_ context.Context, record slog.Record) error {
+	fn := noticeSink.Load()
+	if fn == nil {
+		return nil
+	}
+	if _, dup := noticeSeen.LoadOrStore(record.Message, struct{}{}); dup {
+		return nil
+	}
+	(*fn)("task: %s\n", record.Message)
+	return nil
+}
+
+func (h noticeHandler) WithAttrs([]slog.Attr) slog.Handler { return h }
+
+func (h noticeHandler) WithGroup(string) slog.Handler { return h }
diff --git a/setup.go b/setup.go
index f24f8b8e..b705d675 100644
--- a/setup.go
+++ b/setup.go
@@ -18,6 +18,7 @@ import (
 	"github.com/go-task/task/v3/internal/filepathext"
 	"github.com/go-task/task/v3/internal/logger"
 	"github.com/go-task/task/v3/internal/output"
+	"github.com/go-task/task/v3/internal/templater"
 	"github.com/go-task/task/v3/internal/version"
 	"github.com/go-task/task/v3/taskfile"
 	"github.com/go-task/task/v3/taskfile/ast"
@@ -192,6 +193,9 @@ func (e *Executor) setupLogger() {
 		AssumeYes:  e.AssumeYes,
 		AssumeTerm: e.AssumeTerm,
 	}
+	templater.SetNoticeSink(func(format string, args ...any) {
+		e.Logger.VerboseErrf(logger.Yellow, format, args...)
+	})
 }
 
 func (e *Executor) setupOutput() error {