diff --git a/NEWS.md b/NEWS.md
index 20441a6d..bb74701a 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,6 @@
 # httr2 (development version)
 
+* `req_url_query()` gains the ability to control how spaces are encoded (#432).
 * New `resp_request()` aids debugging by returning the request associated with a response (#604).
 * `print.request()` now correctly escapes `{}` in headers (#586).
 * New `req_headers_redacted()` provides a user-friendlier way to set redacted headers (#561).
diff --git a/R/req-url.R b/R/req-url.R
index cc317dbc..5964532b 100644
--- a/R/req-url.R
+++ b/R/req-url.R
@@ -74,12 +74,17 @@ req_url_relative <- function(req, url) {
 #'   If none of these options work for your needs, you can instead supply a
 #'   function that takes a character vector of argument values and returns a
 #'   a single string.
+#' @param .space How should spaces in query params be escaped? The default,
+#'   "percent", uses standard percent encoding (i.e. `%20`), but you can opt-in
+#'   to "form" encoding, which uses `+` instead.
 req_url_query <- function(.req,
                           ...,
-                          .multi = c("error", "comma", "pipe", "explode")) {
+                          .multi = c("error", "comma", "pipe", "explode"),
+                          .space = c("percent", "form")
+                          ) {
   check_request(.req)
 
-  dots <- multi_dots(..., .multi = .multi)
+  dots <- multi_dots(..., .multi = .multi, .space = .space)
 
   url <- url_parse(.req$url)
   url$query <- modify_list(url$query, !!!dots)
diff --git a/R/url.R b/R/url.R
index cd07befc..0c308f6d 100644
--- a/R/url.R
+++ b/R/url.R
@@ -249,6 +249,7 @@ elements_build <- function(x, name, collapse, error_call = caller_env()) {
 format_query_param <- function(x,
                                name,
                                multi = FALSE,
+                               form = FALSE,
                                error_call = caller_env()) {
   check_query_param(x, name, multi = multi, error_call = error_call)
 
@@ -256,7 +257,11 @@ format_query_param <- function(x,
     unclass(x)
   } else {
     x <- format(x, scientific = FALSE, trim = TRUE, justify = "none")
-    curl::curl_escape(x)
+    x <- curl::curl_escape(x)
+    if (form) {
+      x <- gsub("%20", "+", x, fixed = TRUE)
+    }
+    x
   }
 }
 check_query_param <- function(x, name, multi = FALSE, error_call = caller_env()) {
diff --git a/R/utils-multi.R b/R/utils-multi.R
index aa16e353..3fd851fe 100644
--- a/R/utils-multi.R
+++ b/R/utils-multi.R
@@ -1,5 +1,6 @@
 multi_dots <- function(...,
                        .multi = c("error", "comma", "pipe", "explode"),
+                       .space = c("percent", "form"),
                        error_arg = "...",
                        error_call = caller_env()) {
   if (is.function(.multi)) {
@@ -7,6 +8,8 @@ multi_dots <- function(...,
   } else {
     .multi <- arg_match(.multi, error_arg = ".multi", error_call = error_call)
   }
+  .space <- arg_match(.space, call = error_call)
+  form <- .space == "form"
 
   dots <- list2(...)
   if (length(dots) == 0) {
@@ -31,20 +34,20 @@ multi_dots <- function(...,
   n <- lengths(dots)
   if (any(n > 1)) {
     if (is.function(.multi)) {
-      dots[n > 1] <- imap(dots[n > 1], format_query_param, multi = TRUE)
+    dots[n > 1] <- imap(dots[n > 1], format_query_param, multi = TRUE, form = form)
       dots[n > 1] <- lapply(dots[n > 1], .multi)
       dots[n > 1] <- lapply(dots[n > 1], I)
     } else if (.multi == "comma") {
-      dots[n > 1] <- imap(dots[n > 1], format_query_param, multi = TRUE)
+      dots[n > 1] <- imap(dots[n > 1], format_query_param, multi = TRUE, form = form)
       dots[n > 1] <- lapply(dots[n > 1], paste0, collapse = ",")
       dots[n > 1] <- lapply(dots[n > 1], I)
     } else if (.multi == "pipe") {
-      dots[n > 1] <- imap(dots[n > 1], format_query_param, multi = TRUE)
+      dots[n > 1] <- imap(dots[n > 1], format_query_param, multi = TRUE, form = form)
       dots[n > 1] <- lapply(dots[n > 1], paste0, collapse = "|")
       dots[n > 1] <- lapply(dots[n > 1], I)
     } else if (.multi == "explode") {
       dots <- explode(dots)
-      dots[n > 1] <- imap(dots[n > 1], format_query_param, multi = TRUE)
+      dots[n > 1] <- imap(dots[n > 1], format_query_param, multi = TRUE, form = form)
       dots[n > 1] <- lapply(dots[n > 1], I)
     } else if (.multi == "error") {
       cli::cli_abort(
@@ -58,7 +61,12 @@ multi_dots <- function(...,
   }
 
   # Format other params
-  dots[n == 1] <- imap(dots[n == 1], format_query_param, error_call = error_call)
+  dots[n == 1] <- imap(
+    dots[n == 1],
+    format_query_param,
+    form = form,
+    error_call = error_call
+  )
   dots[n == 1] <- lapply(dots[n == 1], I)
 
   dots
diff --git a/man/req_url.Rd b/man/req_url.Rd
index 933e7a58..a213a4ff 100644
--- a/man/req_url.Rd
+++ b/man/req_url.Rd
@@ -12,7 +12,12 @@ req_url(req, url)
 
 req_url_relative(req, url)
 
-req_url_query(.req, ..., .multi = c("error", "comma", "pipe", "explode"))
+req_url_query(
+  .req,
+  ...,
+  .multi = c("error", "comma", "pipe", "explode"),
+  .space = c("percent", "form")
+)
 
 req_url_path(req, ...)
 
@@ -43,6 +48,10 @@ containing multiple values:
 If none of these options work for your needs, you can instead supply a
 function that takes a character vector of argument values and returns a
 a single string.}
+
+\item{.space}{How should spaces in query params be escaped? The default,
+"percent", uses standard percent encoding (i.e. \verb{\%20}), but you can opt-in
+to "form" encoding, which uses \code{+} instead.}
 }
 \value{
 A modified HTTP \link{request}.
diff --git a/tests/testthat/_snaps/req-url.md b/tests/testthat/_snaps/req-url.md
index aeb5062a..90c05484 100644
--- a/tests/testthat/_snaps/req-url.md
+++ b/tests/testthat/_snaps/req-url.md
@@ -1,3 +1,11 @@
+# can control space handling
+
+    Code
+      req_url_query(req, a = " ", .space = "bar")
+    Condition
+      Error in `multi_dots()`:
+      ! `.space` must be one of "percent" or "form", not "bar".
+
 # can handle multi query params
 
     Code
diff --git a/tests/testthat/test-req-url.R b/tests/testthat/test-req-url.R
index a76ecfa8..759c33a8 100644
--- a/tests/testthat/test-req-url.R
+++ b/tests/testthat/test-req-url.R
@@ -52,6 +52,17 @@ test_that("can set query params", {
   expect_equal(req_url_query(req, !!!list(a = 1, a = 2))$url, "http://example.com/?a=1&a=2")
 })
 
+test_that("can control space handling", {
+  req <- request("http://example.com/")
+  expect_equal(req_url_query(req, a = " ")$url, "http://example.com/?a=%20")
+  expect_equal(req_url_query(req, a = " ", .space = "form")$url, "http://example.com/?a=+")
+
+  expect_snapshot(
+    req_url_query(req, a = " ", .space = "bar"),
+    error = TRUE
+  )
+})
+
 test_that("can handle multi query params", {
   req <- request("http://example.com/")