Except for signed CD dumps, the no.1 in real sales rarely sells more than 2-3,000 either so v. similar to the Compilation Chart in some respect (which of course is also purely real sales in most cases). Anti-Hero made no.1 for the first time this week with sales of 2,445; mainly due to the release of new remixes purchased by download.

I expect very few songs will ever cross the 1 million threshold now unless they are very very close indeed. And Happy won’t reach 2 million for at least the next decade.

From liam.k. 's list,

 

Nearly There

The Beatles - Help! (#1, 1965) 988,000 [OCC: September 2017]

Lionel Richie - Hello (#1, 1984) 965,000 [OCC: September 2017]

Bee Gees - How Deep is Your Love (#3, 1977) 963,000 [OCC: September 2017]

Labrinth feat. Emeli Sande - Beneath Your Beautiful (#1, 2012) 963,000 [OCC: September 2017]

Lady Gaga - Just Dance (#1, 2009) 962,000 [OCC: September 2017]

George Harrison - My Sweet Lord (#1, 1971) 962,000 [OCC: September 2017]

Bastille - Pompeii (#2, 2013) 960,000 [OCC: September 2017]

 

As you say very unlikely to see another "pure" million seller.

Yeah Adele’s Hello was on 949k in 2017 so that could feasibly be very close now, but even with that unless it’s now over 995k it’s going to be a very long slog. 2 songs called Hello saying goodbye to their chances thanks to the market. :D

The OCC says,

This total is unlikely to grow much further, with streams now dominating (audio / video streams account for 98.6% of the singles market in 2022).

 

So very, very few physical sales or downlads for singles these days.

From the Channel 5 programmes in January, the next few from the 1970s and 1980s are:

 

Amazing Grace - 998,509

Mississippi - 980,383

Nothing's Gonna Stop Us Now - 978,580

My Sweet Lord - 975,434

 

Can't see any of those other than perhaps Amazing Grace getting there - NGSUN has increased the most, but still needs to double its sales since 2017. The Beatles' Help! may be close though.