diff --git a/R/cache.R b/R/cache.R
index 89797c259..6cb610b19 100644
--- a/R/cache.R
+++ b/R/cache.R
@@ -1045,7 +1045,7 @@ Cache <-
 #' @keywords internal
 .namesPostProcessFormals <- function() {
   c(
-    "x", "filename1", "filename2", "studyArea", "rasterToMatch",
+    "x", "filename1", "writeTo", "studyArea", "rasterToMatch",
     "overwrite", "useSAcrs", "useCache", "verbose"
   )
 }
diff --git a/R/postProcessTo.R b/R/postProcessTo.R
index a8523ca5d..c8545add8 100644
--- a/R/postProcessTo.R
+++ b/R/postProcessTo.R
@@ -1273,6 +1273,11 @@ remapOldArgs <- function(..., fn = sys.function(sys.parent()), envir = parent.fr
                          verbose = getOption("reproducible.verbose")) {
   forms <- formals(fn)
   dots <- list(...)
+
+  if (!is.null(dots$filename2)) {
+    stop("filename2 arg is deprecated - please pass 'writeTo' instead (see `reproducible::writeTo`")
+  }
+
   dots <- dots[!vapply(dots, is.null, FUN.VALUE = logical(1))]
 
   ret <- list()
diff --git a/R/preProcess.R b/R/preProcess.R
index 46df0b30a..7af664890 100644
--- a/R/preProcess.R
+++ b/R/preProcess.R
@@ -1,5 +1,6 @@
 utils::globalVariables(c(
-  "reproducible.inputPaths", "successfulCheckSumFilePath", "successfulDir"
+  "reproducible.inputPaths", "successfulCheckSumFilePath", "successfulDir",
+  "destinationPathUser"
 ))
 
 #' @param n Number of non-null arguments passed to `preProcess`.
diff --git a/R/prepInputs.R b/R/prepInputs.R
index 87f58f29e..4769cc5a2 100644
--- a/R/prepInputs.R
+++ b/R/prepInputs.R
@@ -45,8 +45,7 @@ utils::globalVariables(c(
 #'     \item Crop using [cropTo()];
 #'     \item Project using [projectTo()];
 #'     \item Mask using [maskTo()];
-#'     \item Determine file name [determineFilename()] via `filename2`;
-#'     \item Optionally, write that file name to disk via [writeTo()].
+#'     \item write the file to disk via [writeTo()].
 #'    }
 #'
 #'   NOTE: checksumming does not occur during the post-processing stage, as
@@ -311,7 +310,7 @@ utils::globalVariables(c(
 #'         studyArea = studyArea,
 #'         fun = "terra::vect",
 #'         destinationPath = dPath,
-#'         filename2 = "EcozoneFile.shp"
+#'         writeTo = "EcozoneFile.shp"
 #'       ) # passed to determineFilename
 #'
 #'       terra::plot(shpEcozone[, 1])
diff --git a/man/prepInputs.Rd b/man/prepInputs.Rd
index 23b450897..9c7c72cc3 100644
--- a/man/prepInputs.Rd
+++ b/man/prepInputs.Rd
@@ -332,7 +332,7 @@ if (requireNamespace("terra", quietly = TRUE) &&
         studyArea = studyArea,
         fun = "terra::vect",
         destinationPath = dPath,
-        filename2 = "EcozoneFile.shp"
+        writeTo = "EcozoneFile.shp"
       ) # passed to determineFilename
 
       terra::plot(shpEcozone[, 1])
diff --git a/tests/testthat/test-cache.R b/tests/testthat/test-cache.R
index 699a04c39..7c9988946 100644
--- a/tests/testthat/test-cache.R
+++ b/tests/testthat/test-cache.R
@@ -1717,7 +1717,7 @@ test_that("Issue 316 - writeOutputs in a non getwd dir", {
   rasterToMatchLarge <- list()
   for (i in 1:2) {
     rasterToMatchLarge[[i]] <- Cache(writeOutputs, rasterToMatch,
-                                     filename2 = .suffix(
+                                     writeTo = .suffix(
                                        file.path(tmpdir, "rasterToMatchLarge.tif"),
                                        paste0("_", studyAreaName)
                                      ), datatype = "INT2U",
diff --git a/tests/testthat/test-prepInputs.R b/tests/testthat/test-prepInputs.R
index fae60c157..2bb6486ca 100644
--- a/tests/testthat/test-prepInputs.R
+++ b/tests/testthat/test-prepInputs.R
@@ -95,7 +95,7 @@ test_that("prepInputs doesn't work (part 1)", {
               alsoExtract = reproducible::asPath(ecozoneFiles),
               studyArea = StudyArea,
               destinationPath = dPath,
-              filename2 = "EcozoneFile.shp",
+              writeTo = "EcozoneFile.shp",
               useCache = FALSE
             ),
             quick = "destinationPath"
@@ -1866,7 +1866,7 @@ test_that("writeOutputs saves factor rasters with .grd class to preserve levels"
   tifTmp <- normPath(tifTmp)
 
   b1 <- suppressWarnings(terra::writeRaster(a, filename = tifTmp, overwrite = TRUE)) # the GDAL>6 issue
-  b1a <- writeOutputs(a, filename2 = tifTmp)
+  b1a <- writeOutputs(a, writeTo = tifTmp)
   expect_equivalent(b1, b1a)
   expect_equivalent(b1[], b1a[])
 
@@ -1903,7 +1903,7 @@ test_that("rasters aren't properly resampled", {
       targetFile = tiftemp1, rasterToMatch = terra::rast(tiftemp2),
       destinationPath = dirname(tiftemp1), method = "bilinear",
       datatype = "INT2S",
-      filename2 = tempfile(tmpdir = tmpdir, fileext = ".tif")
+      writeTo = tempfile(tmpdir = tmpdir, fileext = ".tif")
     )
   }) # about "raster layer has integer values"
 
@@ -1919,7 +1919,7 @@ test_that("rasters aren't properly resampled", {
     out3 <- prepInputs(
       targetFile = tiftemp3, rasterToMatch = terra::rast(tiftemp2),
       destinationPath = dirname(tiftemp3),
-      filename2 = tempfile(tmpdir = tmpdir, fileext = ".tif")
+      writeTo = tempfile(tmpdir = tmpdir, fileext = ".tif")
     )
     expect_true(dataType2(out3) == "FLT4S")
 
@@ -1934,7 +1934,7 @@ test_that("rasters aren't properly resampled", {
     out3 <- prepInputs(
       targetFile = tiftemp4, rasterToMatch = terra::rast(tiftemp2),
       destinationPath = dirname(tiftemp3),
-      filename2 = tempfile(tmpdir = tmpdir, fileext = ".tif")
+      writeTo = tempfile(tmpdir = tmpdir, fileext = ".tif")
     )
     expect_true(is(out3, rasterType()))
     expect_true(identical(length(Filenames(out3)), 1L))
@@ -1947,7 +1947,7 @@ test_that("rasters aren't properly resampled", {
           targetFile = tiftemp4, rasterToMatch = terra::rast(tiftemp2),
           destinationPath = dirname(tiftemp3),
           fun = rasterStackFn,
-          filename2 = c(
+          writeTo = c(
             tempfile(tmpdir = tmpdir, fileext = ".grd"),
             tempfile(tmpdir = tmpdir, fileext = ".grd")
           )
@@ -1971,7 +1971,7 @@ test_that("rasters aren't properly resampled", {
           targetFile = tiftemp5, rasterToMatch = terra::rast(tiftemp2),
           destinationPath = dirname(tiftemp3),
           fun = rasterStackFn,
-          filename2 = c(
+          writeTo = c(
             tempfile(tmpdir = tmpdir, fileext = ".grd"),
             tempfile(tmpdir = tmpdir, fileext = ".grd"),
             tempfile(tmpdir = tmpdir, fileext = ".tif")
@@ -1987,7 +1987,7 @@ test_that("rasters aren't properly resampled", {
           targetFile = tiftemp4, rasterToMatch = terra::rast(tiftemp2),
           destinationPath = dirname(tiftemp3),
           fun = rasterStackFn,
-          filename2 = c(
+          writeTo = c(
             tempfile(tmpdir = tmpdir, fileext = ".grd"),
             tempfile(tmpdir = tmpdir, fileext = ".grd")
           )