diff --git a/R/utils.R b/R/utils.R
index d9be06f..e63da4a 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -2,9 +2,9 @@
 #'
 #' @param data Data frame for resume entry
 #' @param start Start date column name. Default is "start"
-#' @param end End date column name. Default is "end"
-#' @param sep Separator between start and end date. Default is "-"
-#' @param format Date format. Default is "%M %Y"
+#' @param end Optional. End date column name.
+#' @param sep Separator between start and end date. Default is " - "
+#' @param date_format Date format. Default is "%M %Y"
 #' @param colname_date Name for the generated date column. Default is "date"
 #' @param replace_na Value to replace NA values. Default is "Present"
 #' @param sort_by Sort by "none", "start" or "end". Default is "none"
@@ -15,30 +15,41 @@
 #'
 #' @examples
 #' work |>
-#'   format_date(format = "%Y", sort_by = "start") |>
+#'   format_date(end = "end", date_format = "%Y", sort_by = "start") |>
 #'   resume_entry()
 #'
-format_date <- function(data, start = "start", end = "end", sep = "-",
-                        format = "%M %Y",
+
+format_date <- function(data,
+                        start = "start",
+                        end = NULL,
+                        sep = " - ",
+                        date_format = "%M %Y",
                         colname_date = "date",
                         replace_na = "Present",
                         sort_by = "none",
                         decreasing = TRUE) {
-  data[[start]] <- format(data[[start]], format)
-  data[[end]] <- format(data[[end]], format)
 
-  # Replace NA values
+  data[[start]] <- format(data[[start]], date_format)
   data[[start]][is.na(data[[start]])] <- replace_na
-  data[[end]][is.na(data[[end]])] <- replace_na
 
   # Create date column
-  data[[colname_date]] <- paste(data[[start]], data[[end]], sep = sep)
+  if (is.null(end)) {
+    data[[colname_date]] <- data[[start]]
+  } else {
+    data[[end]] <- format(data[[end]], date_format)
+    data[[end]][is.na(data[[end]])] <- replace_na
+    data[[colname_date]] <- paste(data[[start]], data[[end]], sep = sep)
+  }
 
   # Sort
   if (sort_by == "start") {
     data <- data[order(data[[start]], decreasing = decreasing), ]
-  } else if (sort_by == "end") {
+  } else if (sort_by == "end" && !is.null(end)) {
     data <- data[order(data[[end]], decreasing = decreasing), ]
+  } else if (sort_by == "none") {
+    # Do nothing
+  } else {
+    stop("Invalid sort_by value. Use 'none', 'start' or 'end'")
   }
 
   return(data)
diff --git a/README.md b/README.md
index 82aa476..cbff026 100644
--- a/README.md
+++ b/README.md
@@ -112,7 +112,7 @@ work |>
   format_date(
     start = "date_start",
     end = "date_end",
-    format = "%Y",
+    date_format = "%Y",
     sep = "->",
     sort_by = "start"
   ) |>
diff --git a/README.qmd b/README.qmd
index b290a89..de36809 100644
--- a/README.qmd
+++ b/README.qmd
@@ -110,7 +110,7 @@ work |>
   format_date(
     start = "date_start",
     end = "date_end",
-    format = "%Y",
+    date_format = "%Y",
     sep = "->",
     sort_by = "start"
   ) |>
diff --git a/man/format_date.Rd b/man/format_date.Rd
index 7074867..62a619c 100644
--- a/man/format_date.Rd
+++ b/man/format_date.Rd
@@ -7,9 +7,9 @@
 format_date(
   data,
   start = "start",
-  end = "end",
-  sep = "-",
-  format = "\%M \%Y",
+  end = NULL,
+  sep = " - ",
+  date_format = "\%M \%Y",
   colname_date = "date",
   replace_na = "Present",
   sort_by = "none",
@@ -21,11 +21,11 @@ format_date(
 
 \item{start}{Start date column name. Default is "start"}
 
-\item{end}{End date column name. Default is "end"}
+\item{end}{Optional. End date column name.}
 
-\item{sep}{Separator between start and end date. Default is "-"}
+\item{sep}{Separator between start and end date. Default is " - "}
 
-\item{format}{Date format. Default is "\%M \%Y"}
+\item{date_format}{Date format. Default is "\%M \%Y"}
 
 \item{colname_date}{Name for the generated date column. Default is "date"}
 
@@ -43,7 +43,7 @@ Data Column Formatter
 }
 \examples{
 work |>
-  format_date(format = "\%Y", sort_by = "start") |>
+  format_date(end = "end", date_format = "\%Y", sort_by = "start") |>
   resume_entry()
 
 }
diff --git a/vignettes/awesomecv/awesomecv.qmd b/vignettes/awesomecv/awesomecv.qmd
index 5c7030c..5190f24 100644
--- a/vignettes/awesomecv/awesomecv.qmd
+++ b/vignettes/awesomecv/awesomecv.qmd
@@ -57,7 +57,7 @@ resume_entry(pub)
 ```{r}
 #| output: asis
 work |>
-  format_date(format = "%Y", sort_by = "start") |>
+  format_date(end = "end", date_format = "%Y", sort_by = "start") |>
   resume_entry()
 ```