ILR - do I need all my passports?

Hi all

Just a quick question on applying for ILR for those who have been through the process. I’m just getting all my ducks in a row before booking my appointment for March 2018 (just booked my life in the UK test!) and my question is – after receiving FLR(m) in 2015 I got a new US passport as my other one was due to expire, so I’ve had a new one about 2 years now. I’m worried now as I can’t find my old passport anywhere. Obviously I have a separate BRP so it’s not a visa in the passport or anything, but I’m concerned, will I need both my old one and my new one when I apply for ILR?

Thanks so much for any help.

If you find it, you'll include it.  Otherwise just state it's been lost.

Did you keep the same name on your new passport?

Hiya - thanks so much for your reply. I kept my maiden name so no problems there.
Updating because I FOUND my old passport at my in-laws, finally, just before making my ILR appointment next week. However it feels so unusually light and small, it literally almost feels like they ripped pages out when they returned it! I'm not sure if I'm just going crazy because the newer ones are thicker. Do you know if the normal old (issued in 2005) passports are only 24 pages? I can't seem to find this online. I know I am wayyy overthinking this, but I don't want it to look like I tore pages out!

Apparently, as of Jan 2016, they no longer issue 24-page passports to people applying to renew from outside the US - everyone now gets 52 pages to mitigate the need for regular travellers to apply for more pages/new passports:

https://rw.usembassy.gov/extra-visa-pages-u-s-passports-no-longer-issued-effective-january-1-2016/ (this is for Rwanda, but it applies to other countries too)

This must be why I notice the difference so much. I couldn't believe how much lighter it was when I found it! Thanks.