McKay, who is ranked number one in Britain, scored 48.2 in her short programme at the European Figure Skating Championships in Minsk, Belarus, placing her 22nd.
Alina Zagitova from Russia took the top spot, with a score of 75, while her teammate Sofia Samodurova was second with 72.88 and Alexia Paganini is lying in third place with 65.64 points.
McKay, 24, who trains at Ice Dundee with elite coaching team Debi and Simon Briggs, said earlier she hoped to make the top 24 in the short programme, which allows her to compete in the free programme on Friday evening.
She said: "I’m really pleased with the result today and one of my main goals here was to qualify, which I did. I made a mistake at the start of my program which I was surprised about as it’s usually one of my strongest elements in my program but I felt the training I had done back home helped me through the rest of my program.
I'm looking forward to getting back out there on Friday for my free program now."
British pairs couple Zoe Jones and Christopher Boyadji from Swindon lay in last place after their short programme.
The championships will take place at Minsk Ice Arena until Sunday.
Scots ice dancer Lewis Gibson and his partner Lilah Fear will compete for Britain in the short programme of their competition on Friday, while Graham Newberry from London will represent the UK in the men's competition.
Joseph Buckland and Robynne Tweedale will also compete in the ice dance competition on Friday.