Which GRCs will change for upcoming GE?

Redditor u/aranbear made this useful infographic above.

The constitutencies that will change are:

East Coast GRC

Sengkang GRC

Hong Kah North SMC

(maybe) Yuhua SMC

Note that the other constituencies still can be redrawn. Up to the Electoral Boundaries Review Committee (EBRC).

How he know ah?

1. Divide the number of voters by the number of MPs. 2,594,740 electors and 89 elected MPs means 29,154 voters per MP - rounded to 29,200.
   

2. Add 30% to find the upper range (38,000) and minus 30% to find the lower range (20,000). In other words, each MP can only represent between 20,000 - 38,000 voters.
   

3. If the number of voters is too high or low, the boundaries must be redrawn.

Which other GRCs grew/shrank?

The biggest growth was in Hong Kah North (+4,523 voters) and Tampines (+4,112 voters).

The biggest shrinkage was in East Coast (-2,175 voters) and Marine Parade (-1,444 voters).

Overall the pool of voters grew by 3,644 voters.

Once the election boundaries are drawn, it's a sure sign that the elections are around the corner. Keep an eye out!