Average Cost to Seed a Lawn. The average cost to seed a lawn is $1,302. Most homeowners reported that the expense of replanting a lawn was between $989 and $1,615.The lowest amount paid to reseed a lawn was $50, while the highest amount paid was $3,700.A small patching job on a lawn will be at the low end of the spectrum, while covering several acres of dirt with grass seed will be at the high end of pricing.verage Cost to Seed a Lawn. The average cost to seed a lawn is $1,302. Most homeowners reported that the expense of replanting a lawn was between $989 and $1,615.