Since “safe” is being used as a Yes-No binary/boolean here,
IMHO, the only technically correct answer is - corporate bonds are NOT safe
as they carry some risk.
Both the principal repayment and interest payments (if any) can be delayed or missed.
However, corporate bonds maybe safe-er than a few other investments.
Do checkout the rating of the bond to identify riskier bonds to avoid investing in.
The train of thought discussed in this post should help in this matter.
Also, do evaluate whether those additional few percentage points of return (compared to lower-risk investments) are actually worth the additional risk. One way to do that is by estimating the expected utility [1] [2] of various investments.
Source: Retail traders bought record shares in US market yesterday - #6 by cvs
Also, if looking into bonds for safety of principal,
and still targeting a desired rate of return,
consider deploying a Seneca’s barbell portfolio
with a combination of extremely low (zero?) risk, and riskier instruments.
More details on such an approach in this recent discussion thread.
Also, couple of relevant discussion-threads on this topic -
