Acts 22:16 KJV
And now why tarriest thou? arise, and be baptized, and wash away thy sins, calling on the name of the Lord.
Matthew Poole's Commentary says
"as washing causeth the spots to disappear, and to be as if they had not been, Isa_1:18; so does pardoning mercy, or remission of sins, which accompanieth baptism, as in the due receiver, Mat_3:11 1Pe_3:21,22. Where true faith is, together with the profession of it by baptism, there is salvation promised, Mar_16:16. In the mean while it is not the water, (for that only signifies), but it is the blood of Christ, which is thereby signified, that cleanseth us from our sins, as 1Jo_1:7. Yet sacraments are not empty and deceitful signs; but God accompanieth his own ordinances with his power from on high, and makes them effectual for those great things for which he instituted and appointed them."
This verse does not say that baptism washes away sins. It is the calling on the name of the Lord that does that.
No man has to be baptized in order to be saved. The thief on the cross proves that. However, I cannot conceive of a Christian who does not want to follow the Lord in believer's baptism. When we have an excuse such as the thief's then we may well miss baptism. But having opportunity to be baptized in obedience to the Lord, any true believer would naturally follow His Saviour into the water.