diff --git a/local.c b/local.c
index 10a4a993d..df85f8133 100644
--- a/local.c
+++ b/local.c
@@ -104,6 +104,7 @@ static const char * const device_attrs_blacklist[] = {
 static const char * const buffer_attrs_reserved[] = {
 	"length",
 	"enable",
+	"watermark",
 };
 
 static int ioctl_nointr(int fd, unsigned long request, void *data)
@@ -923,6 +924,15 @@ static int local_open(const struct iio_device *dev,
 	if (ret < 0)
 		return ret;
 
+	/*
+	 * Set watermark to the buffer size; the driver will adjust to its
+	 * maximum if it's too high without issueing an error.
+	 */
+	ret = local_write_dev_attr(dev, "buffer/watermark",
+				   buf, strlen(buf) + 1, false);
+	if (ret < 0 && ret != -ENOENT)
+		return ret;
+
 	pdata->cancel_fd = eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
 	if (pdata->cancel_fd == -1)
 		return -errno;