diff --git a/DESCRIPTION b/DESCRIPTION
index fd45ce4c..dd4e2282 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -19,7 +19,10 @@ Authors@R:
       person(given = "Mitchell",
              family = "O'Hara-Wild",
              role = "aut",
-             comment = c(ORCID = "0000-0001-6729-7695")))
+             comment = c(ORCID = "0000-0001-6729-7695")),
+      person(given = "David",
+             family = "Holt",
+             role = "ctb"))
 Description: Provides a 'tbl_ts' class (the 'tsibble') for
     temporal data in an data- and model-oriented format. The 'tsibble'
     provides tools to easily manipulate and analyse temporal data, such as
diff --git a/NEWS.md b/NEWS.md
index 2d365fd1..00ccd9c4 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -2,6 +2,7 @@
 
 * Dropped the support of `summarise_all()`, and made `dplyr::across()` compatible with `summarise.tbl_ts()`.
 * Defunct rolling functions in favour of {slider}.
+* Added input support for `%Y M%M` format to `yearmonth()`. (#142)
 
 # tsibble 0.9.2
 
diff --git a/R/yearmonth.R b/R/yearmonth.R
index 0baf4503..6c21c7ad 100644
--- a/R/yearmonth.R
+++ b/R/yearmonth.R
@@ -65,8 +65,27 @@ yearmonth.Date <- function(x) {
 
 #' @export
 yearmonth.character <- function(x) {
-  assertDate(x)
-  new_yearmonth(anydate(x))
+  key_words <- regmatches(x, gregexpr("[[:alpha:]]+", x))
+  search_expr <- "^[[:digit:]]{1~4}(m|mon|month)[[:digit:]]{1~4}$"
+  if (all(grepl(search_expr, key_words, ignore.case = TRUE))) {
+    yr_mon <- regmatches(x, gregexpr("[[:digit:]]+", x))
+    digits_lgl <- map_lgl(yr_mon, ~ !has_length(.x, 2))
+    digits_len <- map_int(yr_mon, ~ sum(nchar(.x)))
+    digits_ind <- nchar(flatten_chr(yr_mon))
+    if (any(digits_lgl) || any(digits_len < 5) || any(digits_len > 6) || 3 == digits_ind) {
+      abort("Character strings are not in a standard unambiguous format.")
+    }
+    yr_lgl <- map(yr_mon, ~ grepl("[[:digit:]]{4}", .x))
+    yr <- as.integer(map2_chr(yr_mon, yr_lgl, ~ .x[.y]))
+    mon <- as.integer(map2_chr(yr_mon, yr_lgl, ~ .x[!.y]))
+    if (any(mon > 12)) {
+      abort("Months can't be greater than 12.")
+    }
+    yearmonth(12 * (yr - 1970) + mon - 1)
+  } else {
+    assertDate(x)
+    new_yearmonth(anydate(x))
+  }
 }
 
 #' @export
diff --git a/tests/testthat/test-yearmonth.R b/tests/testthat/test-yearmonth.R
index 015e6116..787bf4e0 100644
--- a/tests/testthat/test-yearmonth.R
+++ b/tests/testthat/test-yearmonth.R
@@ -12,6 +12,17 @@ test_that("input types for yearmonth()", {
   expect_identical(yearmonth(c(596, 576)), expected)
 })
 
+test_that("%Ym%M format for yearmonth()", {
+  expect_identical(yearmonth("2018 M01"), yearmonth("2018 Jan"))
+  expect_identical(yearmonth("2018 M1"), yearmonth("2018 Jan"))
+  expect_identical(yearmonth("2018mon01"), yearmonth("2018 Jan"))
+  expect_identical(yearmonth("2018 month 12"), yearmonth("2018 Dec"))
+  expect_error(yearmonth("201M1"))
+  expect_error(yearmonth("2018M13"))
+  expect_error(yearmonth("201M811"))
+  expect_error(yearmonth(c("2018M1", "2018 Feb", "2018M3")))
+})
+
 test_that("vec_arith() for yearmonth()", {
   expect_identical(yearmonth(x) + 1:2, yearmonth(c("2019 Oct", "2018 Mar")))
   expect_identical(yearmonth(x) - 1, yearmonth(c("2019 Aug", "2017 Dec")))