diff --git a/NAMESPACE b/NAMESPACE
index 62c509bf7..75c862260 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -160,6 +160,9 @@ importFrom(fansi,strip_sgr)
 importFrom(fansi,substr2_ctl)
 importFrom(glue,as_glue)
 importFrom(lifecycle,deprecate_soft)
+importFrom(lifecycle,deprecate_warn)
+importFrom(lifecycle,deprecated)
+importFrom(lifecycle,is_present)
 importFrom(utf8,utf8_width)
 importFrom(utils,head)
 importFrom(utils,str)
diff --git a/R/ctl_pillar.R b/R/ctl_pillar.R
index 84dc51d2d..35e70b418 100644
--- a/R/ctl_pillar.R
+++ b/R/ctl_pillar.R
@@ -142,8 +142,7 @@ rowidformat2 <- function(data, names, has_star) {
 #' @inheritParams pillar
 #' @param components A named list of components constructed with [pillar_component()].
 #' @param class Name of subclass.
-#' @param extra For compound pillars, indicate the names or indices of the
-#'   sub-pillars that could not be shown due to width constraints.
+#' @param extra Deprecated.
 #'
 #' @export
 #' @examples
@@ -161,9 +160,14 @@ rowidformat2 <- function(data, names, has_star) {
 #'   lines = new_pillar_component(list(lines("=")), width = 1)
 #' ))
 new_pillar <- function(components, ..., width = NULL, class = NULL,
-                       extra = NULL) {
+                       extra = deprecated()) {
   "!!!!DEBUG new_pillar(`v(width)`, `v(class)`)"
 
+  if (is_present(extra)) {
+    # Signal the deprecation to the user
+    deprecate_warn("1.6.6", "pillar::new_pillar(extra = )")
+  }
+
   check_dots_empty()
   if (length(components) > 0 && !is_named(components)) {
     abort("All components must have names.")
@@ -172,8 +176,7 @@ new_pillar <- function(components, ..., width = NULL, class = NULL,
   structure(
     components,
     width = width,
-    class = c(class, "pillar"),
-    extra = extra
+    class = c(class, "pillar")
   )
 }
 
diff --git a/R/zzz.R b/R/zzz.R
index 7da4068fe..aa950210f 100644
--- a/R/zzz.R
+++ b/R/zzz.R
@@ -3,7 +3,7 @@
 #' @import rlang
 #' @import ellipsis
 #' @importFrom glue as_glue
-#' @importFrom lifecycle deprecate_soft
+#' @importFrom lifecycle deprecate_soft deprecate_warn is_present deprecated
 #' @importFrom vctrs data_frame
 #' @importFrom vctrs new_data_frame
 #' @importFrom vctrs new_list_of
diff --git a/man/new_pillar.Rd b/man/new_pillar.Rd
index ac41e74d2..9c803cc26 100644
--- a/man/new_pillar.Rd
+++ b/man/new_pillar.Rd
@@ -4,7 +4,7 @@
 \alias{new_pillar}
 \title{Construct a custom pillar object}
 \usage{
-new_pillar(components, ..., width = NULL, class = NULL, extra = NULL)
+new_pillar(components, ..., width = NULL, class = NULL, extra = deprecated())
 }
 \arguments{
 \item{components}{A named list of components constructed with \code{\link[=pillar_component]{pillar_component()}}.}
@@ -15,8 +15,7 @@ new_pillar(components, ..., width = NULL, class = NULL, extra = NULL)
 
 \item{class}{Name of subclass.}
 
-\item{extra}{For compound pillars, indicate the names or indices of the
-sub-pillars that could not be shown due to width constraints.}
+\item{extra}{Deprecated.}
 }
 \description{
 \ifelse{html}{\href{https://lifecycle.r-lib.org/articles/stages.html#experimental}{\figure{lifecycle-experimental.svg}{options: alt='[Experimental]'}}}{\strong{[Experimental]}}