diff --git a/NAMESPACE b/NAMESPACE
index bd642ddc3..0a0783231 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -76,6 +76,7 @@ S3method(tbl_format_footer,tbl)
 S3method(tbl_format_header,pillar_tbl_format_setup)
 S3method(tbl_format_header,tbl)
 S3method(tbl_format_setup,tbl)
+S3method(tbl_nrow,tbl)
 S3method(tbl_sum,default)
 S3method(tbl_sum,tbl)
 S3method(type_sum,Surv)
@@ -155,6 +156,7 @@ export(tbl_format_body)
 export(tbl_format_footer)
 export(tbl_format_header)
 export(tbl_format_setup)
+export(tbl_nrow)
 export(tbl_sum)
 export(type_sum)
 import(lifecycle)
diff --git a/R/tbl-format-setup.R b/R/tbl-format-setup.R
index 9311addc0..b8ba2b146 100644
--- a/R/tbl-format-setup.R
+++ b/R/tbl-format-setup.R
@@ -76,7 +76,7 @@ tbl_format_setup <- function(
 
   width <- get_width_print(width)
 
-  n <- get_n_print(n, nrow(x))
+  n <- get_n_print(n, tbl_nrow(x))
 
   max_extra_cols <- get_max_extra_cols(max_extra_cols)
   max_footer_lines <- get_max_footer_lines(max_footer_lines)
@@ -112,7 +112,7 @@ tbl_format_setup.tbl <- function(x, width, ...,
   "!!!!DEBUG tbl_format_setup.tbl()"
 
   # Number of rows
-  rows <- nrow(x)
+  rows <- tbl_nrow(x)
 
   lazy <- is.na(rows)
   if (lazy) {
@@ -183,6 +183,23 @@ tbl_format_setup.tbl <- function(x, width, ...,
   )
 }
 
+#' Number of rows in a tbl object
+#'
+#' This generic will be called by [tbl_format_setup()] to determine the number
+#' of rows in a tbl object.
+#'
+#' @param x A tbl object.
+#' @export
+tbl_nrow <- function(x, ...) {
+  UseMethod("tbl_nrow")
+}
+
+#' @export
+tbl_nrow.tbl <- function(x, ...) {
+  nrow(x)
+}
+
+
 #' Construct a setup object for formatting
 #'
 #' @description
diff --git a/_pkgdown.yml b/_pkgdown.yml
index 6d062d5d5..8a0cf2960 100644
--- a/_pkgdown.yml
+++ b/_pkgdown.yml
@@ -21,6 +21,7 @@ reference:
       - ctl_new_pillar
       - ctl_new_pillar_list
       - tbl_sum
+      - tbl_nrow
       - glimpse
       - format_glimpse
   - title: Formatting pillars
diff --git a/man/tbl_nrow.Rd b/man/tbl_nrow.Rd
new file mode 100644
index 000000000..2082efd57
--- /dev/null
+++ b/man/tbl_nrow.Rd
@@ -0,0 +1,15 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/tbl-format-setup.R
+\name{tbl_nrow}
+\alias{tbl_nrow}
+\title{Number of rows in a tbl object}
+\usage{
+tbl_nrow(x, ...)
+}
+\arguments{
+\item{x}{A tbl object.}
+}
+\description{
+This generic will be called by \code{\link[=tbl_format_setup]{tbl_format_setup()}} to determine the number
+of rows in a tbl object.
+}