The answer is no, especially if it is the "first" 30k in your OA. This is because the first 60k of your CPF monies earns an additional interest on top of prevailing rates so you enjoy an "inversion"- in which your CPF monies would be working harder than that of the loan . HDB loan is 2.5-2.6% interest loan but your 20K in OA will yield you 3.5% so you get more money each time- $180 a year to be exact. In fact, I would suggest a 10k OA to SA transfer so that it can be compounded at 5% yearly, which will x4 in 30 years time! Also, the sum that is withdrawn for paying your HDB will have interest accrued, which means that if you choose to instead of CPF paying you interest , you will "own" yourself interest if you utilise CPF monies for your home loan ! If you sell your property, not only will you have to pay back the principal(30k), you also need to pay back the interest accruded as if it was sitting in your CPF OA. Lastly, your 20k in CPF OA can also act as a back-up plan if you lose your job(touch wood) - it can probably ride you 1-2 years of HDB payment while you look for a job. This safety net will given you a much needed sense of security- imagine trying to secure a job, and worrying about your loan at the same time.