diff --git a/src/avrdude.1 b/src/avrdude.1
index 3650e411..e59c0beb 100644
--- a/src/avrdude.1
+++ b/src/avrdude.1
@@ -612,9 +612,8 @@ USB-only programmers normally do not need the port option be specified as
 they are automatically identified via their vendor and product IDs from
 avrdude.conf or .avrduderc. Only when there are multiple programmers of
 the same type plugged into the host computer is the -P option needed, see
-below. Some -c programmers, however, ignore the -P option altogether, eg,
-pickit2 or teensy; these cannot distinguish multiple plugged-in
-programmers.
+below. Some -c programmers, eg, pickit2, ignore the -P option altogether;
+these cannot distinguish multiple plugged-in programmers.
 .Pp
 Most USB programmers, however, support the command-line syntax -P
 usb[:<vid>:<pid>][:<serialno>] which allows the user to override the
@@ -623,9 +622,9 @@ request a match of the desired device's serial number with <serialno>. The
 match is done after stripping any existing colons from the given serial
 number on the command line, and right-to-left, so only the least
 significant bytes from the serial number need to be given. The JTAG ICE
-mkII, JTAGICE3, SNAP, PICKit5, CH341A and avrftdi programmers are examples
-for this -P port syntax. Some of these in turn, e.g. the CH341A, are not
-capable of matching serial numbers.
+mkII, JTAGICE3, SNAP, PICKit5, CH341A, teensy and avrftdi programmers are
+examples for this -P port syntax. Some of these in turn, e.g. the CH341A
+and teensy are not capable of matching serial numbers.
 .Pp
 If
 .Nm
diff --git a/src/doc/avrdude.texi b/src/doc/avrdude.texi
index a7bcc128..9a9cce8b 100644
--- a/src/doc/avrdude.texi
+++ b/src/doc/avrdude.texi
@@ -839,9 +839,9 @@ USB-only programmers normally do not need the port option be specified as
 they are automatically identified via their vendor and product IDs from
 @code{avrdude.conf} or @code{.avrduderc}. Only when there are multiple
 programmers of the same type plugged into the host computer is the
-@code{-P} option needed, see below. Some @code{-c} programmers, however,
-ignore the @code{-P} option altogether, eg, pickit5 or teensy;
-these cannot distinguish multiple plugged-in programmers.
+@code{-P} option needed, see below. Some @code{-c} programmers, e.g.,
+pickit5, ignore the @code{-P} option altogether; these cannot distinguish
+multiple plugged-in programmers.
 
 Most USB programmers, however, support the command-line syntax  @code{-P
 usb[:@var{vid}:@var{pid}][:@var{serialno}]} which allows the user to
@@ -850,9 +850,10 @@ override the vendor and product IDs with hexadecimal numbers @var{vid} and
 with @var{serialno}. The match is done after stripping any existing colons
 from the given serial number on the command line, and right-to-left, so
 only the least significant bytes from the serial number need to be given.
-The JTAG ICE mkII, JTAGICE3, SNAP, PICKit5, CH341A and avrftdi programmers
-are examples for this @code{-P} port syntax. Some of these in turn, e.g.
-the CH341A, are not capable of matching serial numbers.
+The JTAG ICE mkII, JTAGICE3, SNAP, PICKit5, CH341A, teensy and avrftdi
+programmers are examples for this @code{-P} port syntax. Some of these in
+turn, e.g. the CH341A and teensy, are not capable of matching serial
+numbers.
 
 If avrdude has been configured with libserialport support, a serial port
 can be specified using a predefined serial adapter type in
diff --git a/src/teensy.c b/src/teensy.c
index 306a7c54..23e8c3e5 100644
--- a/src/teensy.c
+++ b/src/teensy.c
@@ -305,28 +305,32 @@ static int teensy_chip_erase(const PROGRAMMER *pgm, const AVRPART *p) {
 }
 
 static int teensy_open(PROGRAMMER *pgm, const char *port) {
+  char serno[64] = {0};
+  unsigned short new_vid = 0, new_pid = 0;
+  int vid, pid, numids;
+
   pmsg_debug("%s(\"%s\")\n", __func__, port);
-  if(!str_caseeq(port, "usb"))
-    pmsg_warning("option -P %s ignored\n", port);
+
+  // Set new_vid, new_pid and/or serno from -P usb[:<vid>:<pid>]
+  if((numids = str_set_vid_pid_serno(port, &new_vid, &new_pid, serno, sizeof serno)) < 0) {
+    pmsg_error("invalid -P %s; drop -P option or use -P usb[:<vid>:<pid>]\n", port);
+    return LIBAVRDUDE_EXIT_FAIL;
+  }
+  if(*serno)
+    pmsg_warning("ignoring serial number %s given in -P %s\n", serno, port);
+
+  // Set vid/pid in following priority: command-line, config, default
+  vid = numids >= 2? new_vid: pgm->usbvid? pgm->usbvid: TEENSY_VID;
+  LNODEID usbpid = lfirst(pgm->usbpid);
+  pid = numids >= 2? new_pid: usbpid? *(int *) ldata(usbpid): TEENSY_PID;
+  if(numids < 2 && usbpid && lnext(usbpid))
+    pmsg_warning("using PID 0x%04x, ignoring remaining PIDs in list\n", pid);
 
   if(pgm->bitclock)
     pmsg_warning("-c %s does not support adjustable bitclock speed; ignoring -B\n", pgmid);
 
   struct pdata *pdata = &my;
 
-  // Determine VID/PID
-  int vid = pgm->usbvid? pgm->usbvid: TEENSY_VID;
-  int pid = TEENSY_PID;
-
-  LNODEID usbpid = lfirst(pgm->usbpid);
-
-  if(usbpid != NULL) {
-    pid = *(int *) ldata(usbpid);
-    if(lnext(usbpid)) {
-      pmsg_error("using PID 0x%04x, ignoring remaining PIDs in list\n", pid);
-    }
-  }
-
   bool show_retry_message = true;
 
   time_t start_time = time(NULL);