Replacing the SSD drive on my xps 13

I realize you are looking to upgrade only to a 256 GB SSD and so my response here is not actually on-point (so nobody designate this as an answer).

I was able to upgrade the SSD on my XPS 13 (9343) to a Transcend 512 GB SATA III 6Gb/s MTS800 80 mm M.2 SSD Solid State Drive TS512GMTS800 It works great.

GSHANI, I hope you find the answer and the SSD you need. Anecdotally I've usually found Crucial's web site to be correct, when it returns compatible recommendations based on a make and model you supply.

There's good tear down instructions for the XPS here. 

Hi there,

I have a 256 SSD on my XPS 9343 and I want to upgarde to a 512 SSD.  How do I do that?

You'll need an M.2 SATA (not PCIe/NVMe on this model) drive.

Physical replacement is detailed in the service manual:

downloads.dell.com/.../xps-13-l321x_owner's manual_en-us.pdf

You can either make an image of your current system using an external drive OR make  your recovery media (link below) to reload the OS onto the new drive. If you choose to image, turn OFF secure boot in system setup (F2 at powerup) before making the image.

www.dell.com/.../SLN297924